diff --git a/README.md b/README.md
index a186717..466431e 100644
--- a/README.md
+++ b/README.md
@@ -25,3 +25,6 @@ You can run the tests with `npm test`.
 ## Debugging
 When running into an old version of the app try to run the following command first:
 `react-native bundle --platform android --dev false --entry-file index.js --bundle-output android/app/src/main/assets/index.android.bundle --assets-dest android/app/src/main/res`
+
+## NFP rules
+More information about how the app calculates fertility status and bleeding predictions in the [wiki on Gitlab](https://gitlab.com/bloodyhealth/drip/wikis/home)
diff --git a/components/chart/day-column.js b/components/chart/day-column.js
index 268df06..630abc8 100644
--- a/components/chart/day-column.js
+++ b/components/chart/day-column.js
@@ -135,4 +135,4 @@ export default class DayColumn extends Component {
       </View>
     )
   }
-}
\ No newline at end of file
+}
diff --git a/components/home.js b/components/home.js
index 6f4ab05..1fa051d 100644
--- a/components/home.js
+++ b/components/home.js
@@ -8,7 +8,7 @@ import {
 import { LocalDate, ChronoUnit } from 'js-joda'
 import styles from '../styles/index'
 import cycleModule from '../lib/cycle'
-import { getOrCreateCycleDay, bleedingDaysSortedByDate, fillWithDummyData, deleteAll } from '../db'
+import { getOrCreateCycleDay, bleedingDaysSortedByDate, fillWithMucusDummyData, fillWithCervixDummyData, deleteAll } from '../db'
 import {bleedingPrediction as labels} from './labels'
 
 const getCycleDayNumber = cycleModule().getCycleDayNumber
@@ -62,8 +62,14 @@ export default class Home extends Component {
           </View>
           <View style={styles.homeButton}>
             <Button
-              onPress={() => fillWithDummyData()}
-              title="fill with example data">
+              onPress={() => fillWithMucusDummyData()}
+              title="fill with example data for mucus&temp">
+            </Button>
+          </View>
+          <View style={styles.homeButton}>
+            <Button
+              onPress={() => fillWithCervixDummyData()}
+              title="fill with example data for cervix&temp">
             </Button>
           </View>
           <View style={styles.homeButton}>
@@ -107,4 +113,4 @@ function determinePredictionText() {
   } else {
     return labels.predictionStartedXDaysLeft(daysToEnd)
   }
-}
\ No newline at end of file
+}
diff --git a/db/fixtures.js b/db/fixtures.js
index a9075f7..fd4a949 100644
--- a/db/fixtures.js
+++ b/db/fixtures.js
@@ -1,6 +1,9 @@
 function convertToSymptoFormat(val) {
   const sympto = { date: val.date }
-  if (val.temperature) sympto.temperature = { value: val.temperature, exclude: false }
+  if (val.temperature) sympto.temperature = {
+    value: val.temperature,
+    exclude: false
+  }
   if (val.mucus) sympto.mucus = {
     value: val.mucus,
     exclude: false,
@@ -11,7 +14,7 @@ function convertToSymptoFormat(val) {
   return sympto
 }
 
-export const cycleWithFhm = [
+export const cycleWithFhmMucus = [
   { date: '2018-07-01', bleeding: 2 },
   { date: '2018-07-02', bleeding: 1 },
   { date: '2018-07-06', temperature: 36.2},
@@ -26,7 +29,7 @@ export const cycleWithFhm = [
   { date: '2018-07-18', temperature: 36.9, mucus: 2 }
 ].map(convertToSymptoFormat).reverse()
 
-export const longAndComplicatedCycle = [
+export const longAndComplicatedCycleWithMucus = [
   { date: '2018-06-01', temperature: 36.6, bleeding: 2 },
   { date: '2018-06-02', temperature: 36.65 },
   { date: '2018-06-04', temperature: 36.6 },
@@ -70,4 +73,71 @@ export const cycleWithTempAndNoMucusShift = [
   { date: '2018-05-24', temperature: 36.85, mucus: 4 },
   { date: '2018-05-26', temperature: 36.8, mucus: 4 },
   { date: '2018-05-27', temperature: 36.9, mucus: 4 }
-].map(convertToSymptoFormat).reverse()
\ No newline at end of file
+].map(convertToSymptoFormat).reverse()
+
+export const cycleWithFhmCervix = [
+  { date: '2018-08-01', bleeding: 2 },
+  { date: '2018-08-02', bleeding: 1 },
+  { date: '2018-08-03', bleeding: 0 },
+  { date: '2018-08-04', bleeding: 0 },
+  { date: '2018-08-05', temperature: 36.07 },
+  { date: '2018-08-06', temperature: 36.2 },
+  { date: '2018-08-07', temperature: 36.35 },
+  { date: '2018-08-08', temperature: 36.4 },
+  { date: '2018-08-09', temperature: 36.3 },
+  { date: '2018-08-10', temperature: 36.45 },
+  { date: '2018-08-11', temperature: 36.45 },
+  { date: '2018-08-12', temperature: 36.7, cervix: { opening: 1, firmness: 1 } },
+  { date: '2018-08-13', temperature: 36.8, cervix: { opening: 0, firmness: 0 } },
+  { date: '2018-08-14', temperature: 36.75, cervix: { opening: 0, firmness: 0 } },
+  { date: '2018-08-15', temperature: 36.9, cervix: { opening: 0, firmness: 0 } },
+  { date: '2018-08-16', temperature: 36.95, cervix: { opening: 0, firmness: 0 } },
+  { date: '2018-08-17', temperature: 36.9, cervix: { opening: 0, firmness: 0 } },
+  { date: '2018-08-18', temperature: 36.9, cervix: { opening: 1, firmness: 0 } }
+].map(convertToSymptoFormat).reverse()
+
+export const longAndComplicatedCycleWithCervix = [
+  { date: '2018-06-01', temperature: 36.6, bleeding: 2 },
+  { date: '2018-06-02', temperature: 36.65 },
+  { date: '2018-06-04', temperature: 36.6 },
+  { date: '2018-06-05', temperature: 36.55 },
+  { date: '2018-06-06', temperature: 36.7, cervix: { opening: 1, firmness: 1 } },
+  { date: '2018-06-09', temperature: 36.5, cervix: { opening: 1, firmness: 1 } },
+  { date: '2018-06-10', temperature: 36.4, cervix: { opening: 1, firmness: 1 } },
+  { date: '2018-06-13', temperature: 36.45, cervix: { opening: 1, firmness: 1 } },
+  { date: '2018-06-14', temperature: 36.5, cervix: { opening: 1, firmness: 1 } },
+  { date: '2018-06-15', temperature: 36.55, cervix: { opening: 0, firmness: 0 } },
+  { date: '2018-06-16', temperature: 36.7, cervix: { opening: 0, firmness: 0 } },
+  { date: '2018-06-17', temperature: 36.65, cervix: { opening: 1, firmness: 1 } },
+  { date: '2018-06-18', temperature: 36.75, cervix: { opening: 0, firmness: 0 } },
+  { date: '2018-06-19', temperature: 36.8, cervix: { opening: 1, firmness: 0 } },
+  { date: '2018-06-20', temperature: 36.85, cervix: { opening: 0, firmness: 0 } },
+  { date: '2018-06-21', temperature: 36.8, cervix: { opening: 0, firmness: 0 } },
+  { date: '2018-06-22', temperature: 36.9, cervix: { opening: 0, firmness: 0 } },
+  { date: '2018-06-25', temperature: 36.9, cervix: { opening: 0, firmness: 0 } },
+  { date: '2018-06-26', temperature: 36.8, cervix: { opening: 1, firmness: 1 } },
+  { date: '2018-06-27', temperature: 36.9, cervix: { opening: 1, firmness: 1 } }
+].map(convertToSymptoFormat).reverse()
+
+export const cycleWithTempAndNoCervixShift = [
+  { date: '2018-07-01', temperature: 36.6, bleeding: 2 },
+  { date: '2018-07-02', temperature: 36.65 },
+  { date: '2018-07-05', temperature: 36.55 },
+  { date: '2018-07-06', temperature: 36.7, cervix: { opening: 0, firmness: 0 } },
+  { date: '2018-07-08', temperature: 36.45, cervix: { opening: 0, firmness: 0 } },
+  { date: '2018-07-09', temperature: 36.5, cervix: { opening: 1, firmness: 1 }  },
+  { date: '2018-07-10', temperature: 36.4, cervix: { opening: 0, firmness: 0 } },
+  { date: '2018-07-11', temperature: 36.5, cervix: { opening: 0, firmness: 1 }  },
+  { date: '2018-07-13', temperature: 36.45, cervix: { opening: 0, firmness: 1 }  },
+  { date: '2018-07-14', temperature: 36.5, cervix: { opening: 1, firmness: 1 }  },
+  { date: '2018-07-15', temperature: 36.55, cervix: { opening: 1, firmness: 1 }  },
+  { date: '2018-07-16', temperature: 36.7, cervix: { opening: 0, firmness: 1 }  },
+  { date: '2018-07-17', temperature: 36.65, cervix: { opening: 0, firmness: 1 }  },
+  { date: '2018-07-18', temperature: 36.75, cervix: { opening: 1, firmness: 1 }  },
+  { date: '2018-07-19', temperature: 36.8, cervix: { opening: 1, firmness: 1 }  },
+  { date: '2018-07-20', temperature: 36.85, cervix: { opening: 1, firmness: 1 }  },
+  { date: '2018-07-23', temperature: 36.9, cervix: { opening: 0, firmness: 1 }  },
+  { date: '2018-07-24', temperature: 36.85, cervix: { opening: 1, firmness: 1 }  },
+  { date: '2018-07-26', temperature: 36.8, cervix: { opening: 1, firmness: 1 }  },
+  { date: '2018-07-27', temperature: 36.9, cervix: { opening: 1, firmness: 1 }  }
+].map(convertToSymptoFormat).reverse()
diff --git a/db/index.js b/db/index.js
index 1845674..1b79d7b 100644
--- a/db/index.js
+++ b/db/index.js
@@ -1,9 +1,12 @@
 import Realm from 'realm'
 import { LocalDate, ChronoUnit } from 'js-joda'
 import {
+  cycleWithFhmMucus,
+  longAndComplicatedCycleWithMucus,
   cycleWithTempAndNoMucusShift,
-  cycleWithFhm,
-  longAndComplicatedCycle
+  cycleWithFhmCervix,
+  longAndComplicatedCycleWithCervix,
+  cycleWithTempAndNoCervixShift
 } from './fixtures'
 
 const TemperatureSchema = {
@@ -179,10 +182,10 @@ function getCycleDay(localDate) {
   return db.objectForPrimaryKey('CycleDay', localDate)
 }
 
-function fillWithDummyData() {
+function fillWithMucusDummyData() {
   const dummyCycles = [
-    cycleWithFhm,
-    longAndComplicatedCycle,
+    cycleWithFhmMucus,
+    longAndComplicatedCycleWithMucus,
     cycleWithTempAndNoMucusShift
   ]
 
@@ -204,6 +207,32 @@ function fillWithDummyData() {
   })
 }
 
+function fillWithCervixDummyData() {
+  const dummyCycles = [
+    cycleWithFhmCervix,
+    longAndComplicatedCycleWithCervix,
+    cycleWithTempAndNoCervixShift
+  ]
+
+  db.write(() => {
+    db.deleteAll()
+    dummyCycles.forEach(cycle => {
+      cycle.forEach(day => {
+        const existing = getCycleDay(day.date)
+        if (existing) {
+          Object.keys(day).forEach(key => {
+            if (key === 'date') return
+            existing[key] = day[key]
+          })
+        } else {
+          db.create('CycleDay', day)
+        }
+      })
+    })
+  })
+}
+
+
 function deleteAll() {
   db.write(() => {
     db.deleteAll()
@@ -266,7 +295,8 @@ export {
   bleedingDaysSortedByDate,
   temperatureDaysSortedByDate,
   cycleDaysSortedByDate,
-  fillWithDummyData,
+  fillWithMucusDummyData,
+  fillWithCervixDummyData,
   deleteAll,
   getPreviousTemperature,
   getCycleDay,
diff --git a/lib/sympto/cervix.js b/lib/sympto/cervix.js
new file mode 100644
index 0000000..2578381
--- /dev/null
+++ b/lib/sympto/cervix.js
@@ -0,0 +1,52 @@
+export default function (cycleDays, tempEvalEndIndex) {
+  const notDetected = { detected: false }
+  const cervixDays = cycleDays
+    .filter(day => day.cervix && !day.cervix.exclude)
+    .filter(day => typeof day.cervix.opening === 'number' && typeof day.cervix.firmness === 'number')
+
+  // we search for the day of cervix peak, which must:
+  // * have fertile cervix values
+  // * be followed by at least 3 days
+  // these 3 following days must all show infertile cervix values
+  // if everything applies we must check the days until the end of temperature evaluation
+  // during these relevantDays no fertile cervix must occur
+
+  for (let i = 0; i < cervixDays.length; i++) {
+    const day = cervixDays[i]
+    if (isClosedAndHard(day.cervix)) continue
+
+    // the three following days must be with closed and hard cervix (indicating an infertile cervix)
+    const threeFollowingDays = cervixDays.slice(i + 1, i + 4)
+    if (threeFollowingDays.length < 3) continue
+
+    // no other fertile cervix value may occur until temperature evaluation has
+    // been completed
+    const fertileCervixOccursIn3FollowingDays = threeFollowingDays.some(day => {
+      return !isClosedAndHard(day.cervix)
+    })
+    if (fertileCervixOccursIn3FollowingDays) continue
+
+    const cycleDayIndex = cycleDays.indexOf(day)
+    const relevantDays = cycleDays
+      .slice(cycleDayIndex + 1, tempEvalEndIndex + 1)
+      .filter(day => day.cervix && !day.cervix.exclude)
+
+    const onlyClosedAndHardUntilEndOfTempEval = relevantDays.every(day => {
+      return isClosedAndHard(day.cervix)
+    })
+
+    if (onlyClosedAndHardUntilEndOfTempEval) {
+      return {
+        detected: true,
+        cervixPeakBeforeShift: day,
+        evaluationCompleteDay: threeFollowingDays[threeFollowingDays.length - 1]
+      }
+    }
+  }
+
+  return notDetected
+}
+
+function isClosedAndHard (cervixDay) {
+  return cervixDay.opening === 0 && cervixDay.firmness === 0
+}
diff --git a/lib/sympto/index.js b/lib/sympto/index.js
index c85b3ca..575b608 100644
--- a/lib/sympto/index.js
+++ b/lib/sympto/index.js
@@ -1,11 +1,12 @@
 import getTemperatureShift from './temperature'
 import getMucusShift from './mucus'
+import getCervixShift from './cervix'
 import getPreOvulatoryPhase from './pre-ovulatory'
 import { LocalDate } from 'js-joda'
 import assert from 'assert'
 
-export default function getSymptoThermalStatus(cycles) {
-  const { cycle, previousCycle, earlierCycles = [] } = cycles
+export default function getSymptoThermalStatus(cycleInfo) {
+  const { cycle, previousCycle, earlierCycles = [], secondarySymptom = 'mucus' } = cycleInfo
   throwIfArgsAreNotInRequiredFormat([cycle, ...earlierCycles])
 
   const status = {
@@ -15,7 +16,10 @@ export default function getSymptoThermalStatus(cycles) {
   // if there was no first higher measurement in the previous cycle,
   // no infertile pre-ovulatory phase may be assumed
   if (previousCycle) {
-    const statusForLast = getSymptoThermalStatus({ cycle: previousCycle })
+    const statusForLast = getSymptoThermalStatus({
+      cycle: previousCycle,
+      secondarySymptom: secondarySymptom
+    })
     if (statusForLast.temperatureShift) {
       const preOvuPhase = getPreOvulatoryPhase(
         cycle,
@@ -48,20 +52,28 @@ export default function getSymptoThermalStatus(cycles) {
   }
 
   const temperatureShift = getTemperatureShift(cycle)
+
   if (!temperatureShift.detected) return status
 
   const tempEvalEndIndex = cycle.indexOf(temperatureShift.evaluationCompleteDay)
-  const mucusShift = getMucusShift(cycle, tempEvalEndIndex)
-  if (!mucusShift.detected) return status
+
+  let secondaryShift
+  if (secondarySymptom === 'mucus') {
+    secondaryShift = getMucusShift(cycle, tempEvalEndIndex)
+  } else if (secondarySymptom === 'cervix') {
+    secondaryShift = getCervixShift(cycle, tempEvalEndIndex)
+  }
+
+  if (!secondaryShift.detected) return status
 
   let periOvulatoryEnd
   const tempOver = temperatureShift.evaluationCompleteDay.date
-  const mucusOver = mucusShift.evaluationCompleteDay.date
+  const secondarySymptomOver = secondaryShift.evaluationCompleteDay.date
 
-  if (tempOver > mucusOver) {
+  if (tempOver >= secondarySymptomOver) {
     periOvulatoryEnd = temperatureShift.evaluationCompleteDay
-  } else {
-    periOvulatoryEnd = mucusShift.evaluationCompleteDay
+  } else if (secondarySymptom > tempOver) {
+    periOvulatoryEnd = secondaryShift.evaluationCompleteDay
   }
 
   const previousPeriDays = periPhase.cycleDays
@@ -78,7 +90,12 @@ export default function getSymptoThermalStatus(cycles) {
   periPhase.cycleDays = previousPeriDays.slice(0, previousPeriEndIndex + 1)
   periPhase.end = status.phases.postOvulatory.start
 
-  status.mucusShift = mucusShift
+  if (secondarySymptom === 'mucus') {
+    status.mucusShift = secondaryShift
+  } else if (secondarySymptom === 'cervix') {
+    status.cervixShift = secondaryShift
+  }
+
   status.temperatureShift = temperatureShift
 
   return status
@@ -86,18 +103,23 @@ export default function getSymptoThermalStatus(cycles) {
 
 function throwIfArgsAreNotInRequiredFormat(cycles) {
   cycles.forEach(cycle => {
-    assert.ok(Array.isArray(cycle))
-    assert.ok(cycle.length > 0)
-    assert.ok(cycle[0].bleeding !== null)
-    assert.equal(typeof cycle[0].bleeding, 'object')
-    assert.equal(typeof cycle[0].bleeding.value, 'number')
+    assert.ok(Array.isArray(cycle), "Cycles must be arrays.")
+    assert.ok(cycle.length > 0, "Cycle must not be empty.")
+    assert.ok(cycle[0].bleeding !== null, "First cycle day should have bleeding.")
+    assert.equal(typeof cycle[0].bleeding, 'object', "First cycle day must contain bleeding value.")
+    assert.equal(typeof cycle[0].bleeding.value, 'number', "First cycle day bleeding value must be a number.")
     cycle.forEach(day => {
-      assert.equal(typeof day.date, 'string')
-      assert.doesNotThrow(() => LocalDate.parse(day.date))
-      if (day.temperature) assert.equal(typeof day.temperature.value, 'number')
-      if (day.mucus) assert.equal(typeof day.mucus.value, 'number')
-      if (day.mucus) assert.ok(day.mucus.value >= 0)
-      if (day.mucus) assert.ok(day.mucus.value < 5)
+      assert.equal(typeof day.date, 'string', "Date must be given as a string.")
+      assert.doesNotThrow(() => LocalDate.parse(day.date), "Date must be given in right string format.")
+      if (day.temperature) assert.equal(typeof day.temperature.value, 'number', "Temperature value must be a number.")
+      if (day.mucus) assert.equal(typeof day.mucus.value, 'number', "Mucus value must be a number.")
+      if (day.mucus) assert.ok(day.mucus.value >= 0, "Mucus value must greater or equal to 0.")
+      if (day.mucus) assert.ok(day.mucus.value <= 4, "Mucus value must be below 5.")
+      if (day.cervix) assert.ok(day.cervix.opening >= 0, "Cervix opening value must be 0 or bigger")
+      if (day.cervix) assert.ok(day.cervix.opening <= 2, "Cervix opening value must be 2 or smaller")
+      if (day.cervix) assert.ok(day.cervix.firmness >= 0, "Cervix firmness value must be 0 or bigger")
+      if (day.cervix) assert.ok(day.cervix.firmness <= 1, "Cervix firmness value must be 1 or smaller")
+      assert.equal(typeof cycle[0].bleeding.value, 'number', "Bleeding value must be a number")
     })
   })
-}
\ No newline at end of file
+}
diff --git a/lib/sympto/pre-ovulatory.js b/lib/sympto/pre-ovulatory.js
index b1e7698..874e2bc 100644
--- a/lib/sympto/pre-ovulatory.js
+++ b/lib/sympto/pre-ovulatory.js
@@ -12,8 +12,8 @@ export default function(cycle, previousCycles) {
   const maybePreOvuDays = cycle.slice(0, preOvuPhaseLength).filter(d => {
     return d.date <= preOvuEndDate
   })
-  const preOvulatoryDays = getDaysUntilFertileMucus(maybePreOvuDays)
-  // if mucus occurs on the 1st cycle day, there is no pre-ovu phase
+  const preOvulatoryDays = getDaysUntilFertileSecondarySymptom(maybePreOvuDays)
+  // if fertile mucus or cervix occurs on the 1st cycle day, there is no pre-ovu phase
   if (!preOvulatoryDays.length) return null
 
   let endDate
@@ -34,13 +34,17 @@ export default function(cycle, previousCycles) {
   }
 }
 
-function getDaysUntilFertileMucus(days) {
-  const firstFertileMucusDayIndex = days.findIndex(day => {
-    return day.mucus && day.mucus.value > 1
+function getDaysUntilFertileSecondarySymptom(days, secondarySymptom = 'mucus') {
+  const firstFertileSecondarySymptomDayIndex = days.findIndex(day => {
+    if (secondarySymptom === 'mucus') {
+      return day.mucus && day.mucus.value > 1
+    } else if (secondarySymptom === 'cervix') {
+      return day.cervix && !day.cervix.isClosedAndHard
+    }
   })
 
-  if (firstFertileMucusDayIndex > -1) {
-    return days.slice(0, firstFertileMucusDayIndex)
+  if (firstFertileSecondarySymptomDayIndex > -1) {
+    return days.slice(0, firstFertileSecondarySymptomDayIndex)
   }
   return days
-}
\ No newline at end of file
+}
diff --git a/lib/sympto/temperature.js b/lib/sympto/temperature.js
index 387cd63..fb380b5 100644
--- a/lib/sympto/temperature.js
+++ b/lib/sympto/temperature.js
@@ -39,18 +39,18 @@ function checkIfFirstHighMeasurement(temp, i, temperatureDays, ltl) {
   if (i > temperatureDays.length - 3) {
     return { detected: false }
   }
-  const nextDays = temperatureDays.slice(i + 1, i + 4)
+  const nextDaysAfterPotentialFhm = temperatureDays.slice(i + 1, i + 4)
 
   return (
-    getResultForRegularRule(nextDays, ltl)) ||
-    getResultForFirstExceptionRule(nextDays, ltl) ||
-    getResultForSecondExceptionRule(nextDays, ltl) ||
+    getResultForRegularRule(nextDaysAfterPotentialFhm, ltl)) ||
+    getResultForFirstExceptionRule(nextDaysAfterPotentialFhm, ltl) ||
+    getResultForSecondExceptionRule(nextDaysAfterPotentialFhm, ltl) ||
     { detected: false }
 }
 
-function getResultForRegularRule(nextDays, ltl) {
-  if (!nextDays.every(day => day.temp > ltl)) return false
-  const thirdDay = nextDays[1]
+function getResultForRegularRule(nextDaysAfterPotentialFhm, ltl) {
+  if (!nextDaysAfterPotentialFhm.every(day => day.temp > ltl)) return false
+  const thirdDay = nextDaysAfterPotentialFhm[1]
   if (rounded(thirdDay.temp - ltl, 0.1) < 0.2) return false
   return {
     detected: true,
@@ -60,10 +60,10 @@ function getResultForRegularRule(nextDays, ltl) {
   }
 }
 
-function getResultForFirstExceptionRule(nextDays, ltl) {
-  if (nextDays.length < 3) return false
-  if (!nextDays.every(day => day.temp > ltl)) return false
-  const fourthDay = nextDays[2]
+function getResultForFirstExceptionRule(nextDaysAfterPotentialFhm, ltl) {
+  if (nextDaysAfterPotentialFhm.length < 3) return false
+  if (!nextDaysAfterPotentialFhm.every(day => day.temp > ltl)) return false
+  const fourthDay = nextDaysAfterPotentialFhm[2]
   if (fourthDay.temp <= ltl) return false
   return {
     detected: true,
@@ -73,10 +73,10 @@ function getResultForFirstExceptionRule(nextDays, ltl) {
   }
 }
 
-function getResultForSecondExceptionRule(nextDays, ltl) {
-  if (nextDays.length < 3) return false
-  if (secondOrThirdTempIsAtOrBelowLtl(nextDays, ltl)) {
-    const fourthDay = nextDays[2]
+function getResultForSecondExceptionRule(nextDaysAfterPotentialFhm, ltl) {
+  if (nextDaysAfterPotentialFhm.length < 3) return false
+  if (secondOrThirdTempIsAtOrBelowLtl(nextDaysAfterPotentialFhm, ltl)) {
+    const fourthDay = nextDaysAfterPotentialFhm[2]
     if (rounded(fourthDay.temp - ltl, 0.1) >= 0.2) {
       return {
         detected: true,
@@ -89,9 +89,9 @@ function getResultForSecondExceptionRule(nextDays, ltl) {
   return false
 }
 
-function secondOrThirdTempIsAtOrBelowLtl(nextDays, ltl) {
-  const secondIsLow = nextDays[0].temp <= ltl
-  const thirdIsLow = nextDays[1].temp <= ltl
+function secondOrThirdTempIsAtOrBelowLtl(nextDaysAfterPotentialFhm, ltl) {
+  const secondIsLow = nextDaysAfterPotentialFhm[0].temp <= ltl
+  const thirdIsLow = nextDaysAfterPotentialFhm[1].temp <= ltl
   if ((secondIsLow || thirdIsLow) && !(secondIsLow && thirdIsLow)) {
     return true
   } else {
diff --git a/test/sympto/cervix-temp-fixtures.js b/test/sympto/cervix-temp-fixtures.js
new file mode 100644
index 0000000..58ff695
--- /dev/null
+++ b/test/sympto/cervix-temp-fixtures.js
@@ -0,0 +1,188 @@
+function convertToSymptoFormat(val) {
+  const sympto = { date: val.date }
+  if (val.temperature) sympto.temperature = {
+    value: val.temperature,
+    exclude: false
+  }
+
+  if (val.cervix && typeof val.cervix.opening === 'number' && typeof val.cervix.firmness === 'number') sympto.cervix = {
+    opening: val.cervix.opening,
+    firmness: val.cervix.firmness,
+    exclude: false
+  }
+  if (val.bleeding) sympto.bleeding = {
+    value: val.bleeding,
+    exclude: false
+  }
+  return sympto
+}
+
+export const cervixShiftAndFhmOnSameDay = [
+  { date: '2018-08-01', bleeding: 1, cervix: { opening: 1, firmness: 1 } },
+  { date: '2018-08-02', bleeding: 2, cervix: { opening: 1, firmness: 1 } },
+  { date: '2018-08-03', temperature: 36.6, bleeding: 2, cervix: { opening: 2, firmness: 1 } },
+  { date: '2018-08-04', temperature: 36.55, bleeding: 1, cervix: { opening: 2, firmness: 0 } },
+  { date: '2018-08-05', temperature: 36.6, cervix: { opening: 0, firmness: 1 } },
+  { date: '2018-08-06', temperature: 36.65, cervix: { opening: 0, firmness: 1 } },
+  { date: '2018-08-07', temperature: 36.71, cervix: { opening: 1, firmness: 0 } },
+  { date: '2018-08-08', temperature: 36.69, cervix: { opening: 1, firmness: 0 } },
+  { date: '2018-08-09', temperature: 36.64, cervix: { opening: 1, firmness: 1 } },
+  { date: '2018-08-10', temperature: 36.66, cervix: { opening: 1, firmness: 1 } },
+  { date: '2018-08-11', temperature: 36.61, cervix: { opening: 1, firmness: 0 } },
+  { date: '2018-08-12', temperature: 36.6, cervix: { opening: 0, firmness: 1 } },
+  { date: '2018-08-13', temperature: 36.8, cervix: { opening: 0, firmness: 0 } },
+  { date: '2018-08-14', temperature: 36.85, cervix: { opening: 0, firmness: 0 } },
+  { date: '2018-08-15', temperature: 36.9, cervix: { opening: 0, firmness: 0 } },
+  { date: '2018-08-16', temperature: 36.95, cervix: { opening: 0, firmness: 0 } },
+  { date: '2018-08-17', temperature: 36.95, cervix: { opening: 0, firmness: 0 } }
+].map(convertToSymptoFormat)
+
+export const cycleWithFhmNoCervixShift = [
+  { date: '2018-08-01', bleeding: 1 },
+  { date: '2018-08-02', bleeding: 2 },
+  { date: '2018-08-03', temperature: 36.6, bleeding: 2 },
+  { date: '2018-08-04', temperature: 36.55, bleeding: 1 },
+  { date: '2018-08-05', temperature: 36.6 },
+  { date: '2018-08-06', temperature: 36.65, cervix: { opening: 0, firmness: 1 } },
+  { date: '2018-08-07', temperature: 36.7, cervix: { opening: 1, firmness: 0 } },
+  { date: '2018-08-08', temperature: 36.6, cervix: { opening: 0, firmness: 1 } },
+  { date: '2018-08-09', temperature: 36.8, cervix: { opening: 0, firmness: 0 } },
+  { date: '2018-08-10', temperature: 36.85, cervix: { opening: 2, firmness: 0 } },
+  { date: '2018-08-11', temperature: 36.9, cervix: { opening: 1, firmness: 0 } },
+  { date: '2018-08-12', temperature: 36.95, cervix: { opening: 0, firmness: 1 } },
+  { date: '2018-08-13', temperature: 36.95, cervix: { opening: 0, firmness: 0 } }
+].map(convertToSymptoFormat)
+
+export const cycleWithoutFhmNoCervixShift = [
+  { date: '2018-06-02', temperature: 36.6, bleeding: 2 },
+  { date: '2018-06-03', temperature: 36.65 },
+  { date: '2018-06-04', temperature: 36.6 },
+  { date: '2018-06-05', temperature: 36.55 },
+  { date: '2018-06-06', temperature: 36.7, cervix: { opening: 0, firmness: 0 } },
+  { date: '2018-06-09', temperature: 36.8 },
+  { date: '2018-06-10', temperature: 36.9, cervix: { opening: 2, firmness: 0 } },
+  { date: '2018-06-13', temperature: 36.9, cervix: { opening: 1, firmness: 1 } }
+].map(convertToSymptoFormat)
+
+export const longCycleWithoutAnyShifts = [
+  { date: '2018-07-01', temperature: 36.65, bleeding: 1 },
+  { date: '2018-07-02', temperature: 36.45 },
+  { date: '2018-07-03', temperature: 36.65 },
+  { date: '2018-07-04', temperature: 36.65 },
+  { date: '2018-07-05', temperature: 36.65, cervix: { opening: 0, firmness: 0 } },
+  { date: '2018-07-06', temperature: 36.85, cervix: { opening: 0, firmness: 1 } },
+  { date: '2018-07-07', temperature: 36.65, cervix: { opening: 1, firmness: 1 } },
+  { date: '2018-07-08', temperature: 36.65, cervix: { opening: 2, firmness: 1 } },
+  { date: '2018-07-09', temperature: 36.65, cervix: { opening: 2, firmness: 1 } },
+  { date: '2018-07-10', temperature: 36.65, cervix: { opening: 1, firmness: 1 } },
+  { date: '2018-07-11', temperature: 36.35, cervix: { opening: 0, firmness: 0 } },
+  { date: '2018-07-12', temperature: 36.65, cervix: { opening: 0, firmness: 0 } },
+  { date: '2018-07-13', temperature: 36.25, cervix: { opening: 1, firmness: 1 } },
+  { date: '2018-07-14', temperature: 36.65, cervix: { opening: 1, firmness: 1 } },
+  { date: '2018-07-15', temperature: 36.65, cervix: { opening: 2, firmness: 0 } },
+  { date: '2018-07-16', temperature: 36.15, cervix: { opening: 2, firmness: 1 } },
+  { date: '2018-07-17', temperature: 36.65, cervix: { opening: 0, firmness: 1 } },
+  { date: '2018-07-18', temperature: 36.25, cervix: { opening: 2, firmness: 1 } },
+  { date: '2018-07-19', temperature: 36.65, cervix: { opening: 1, firmness: 1 } },
+  { date: '2018-07-20', temperature: 36.45, cervix: { opening: 1, firmness: 1 } },
+  { date: '2018-07-21', temperature: 36.52, cervix: { opening: 0, firmness: 0 } },
+  { date: '2018-07-22', temperature: 36.65, cervix: { opening: 1, firmness: 1 } },
+  { date: '2018-07-23', temperature: 36.75, cervix: { opening: 1, firmness: 1 } },
+  { date: '2018-07-24', temperature: 36.65, cervix: { opening: 1, firmness: 1 } },
+  { date: '2018-07-25', temperature: 36.65, cervix: { opening: 0, firmness: 1 } },
+  { date: '2018-07-26', temperature: 36.65, cervix: { opening: 2, firmness: 1 } },
+].map(convertToSymptoFormat)
+
+export const longAndComplicatedCycle = [
+  { date: '2018-06-01', temperature: 36.6, bleeding: 2 },
+  { date: '2018-06-02', temperature: 36.65 },
+  { date: '2018-06-04', temperature: 36.6 },
+  { date: '2018-06-05', temperature: 36.55 },
+  { date: '2018-06-06', temperature: 36.7, cervix: { opening: 0, firmness: 0 } },
+  { date: '2018-06-09', temperature: 36.5, cervix: { opening: 2, firmness: 1 } },
+  { date: '2018-06-10', temperature: 36.4, cervix: { opening: 2, firmness: 1 } },
+  { date: '2018-06-13', temperature: 36.45, cervix: { opening: 1, firmness: 1 } },
+  { date: '2018-06-14', temperature: 36.5, cervix: { opening: 1, firmness: 1 } },
+  { date: '2018-06-15', temperature: 36.55, cervix: { opening: 1, firmness: 1 } },
+  { date: '2018-06-16', temperature: 36.7, cervix: { opening: 2, firmness: 1 } },
+  { date: '2018-06-17', temperature: 36.65, cervix: { opening: 2, firmness: 1 } },
+  { date: '2018-06-18', temperature: 36.75, cervix: { opening: 1, firmness: 1 } },
+  { date: '2018-06-19', temperature: 36.8, cervix: { opening: 0, firmness: 0 } },
+  { date: '2018-06-20', temperature: 36.85, cervix: { opening: 1, firmness: 1 } },
+  { date: '2018-06-21', temperature: 36.8, cervix: { opening: 1, firmness: 1 } },
+  { date: '2018-06-22', temperature: 36.9, cervix: { opening: 2, firmness: 1 } },
+  { date: '2018-06-25', temperature: 36.9, cervix: { opening: 0, firmness: 0 } },
+  { date: '2018-06-26', temperature: 36.8, cervix: { opening: 0, firmness: 0 } },
+  { date: '2018-06-27', temperature: 36.9, cervix: { opening: 0, firmness: 0 } }
+].map(convertToSymptoFormat)
+
+export const tempShift3DaysAfterCervixShift = [
+  { date: '2018-05-08', bleeding: 3 },
+  { date: '2018-05-09', bleeding: 2 },
+  { date: '2018-05-10', bleeding: 2 },
+  { date: '2018-05-11', bleeding: 1 },
+  { date: '2018-05-12', temperature: 36.3 },
+  { date: '2018-05-13', temperature: 36.4, cervix: { opening: 1, firmness: 1 } },
+  { date: '2018-05-14', temperature: 36.3, cervix: { opening: 1, firmness: 1 } },
+  { date: '2018-05-15', temperature: 36.2, cervix: { opening: 1, firmness: 1 } },
+  { date: '2018-05-16', temperature: 36.3, cervix: { opening: 0, firmness: 0 } },
+  { date: '2018-05-17', temperature: 36.3, cervix: { opening: 0, firmness: 0 } },
+  { date: '2018-05-18', temperature: 36.35, cervix: { opening: 0, firmness: 0 } },
+  { date: '2018-05-19', temperature: 36.65, cervix: { opening: 0, firmness: 0 } },
+  { date: '2018-05-20', temperature: 36.7, cervix: { opening: 0, firmness: 0 } },
+  { date: '2018-05-21', temperature: 36.6, cervix: { opening: 0, firmness: 0 } },
+  { date: '2018-05-22', temperature: 36.85, cervix: { opening: 0, firmness: 0 } },
+  { date: '2018-05-23', temperature: 36.8, cervix: { opening: 1, firmness: 0 } },
+  { date: '2018-05-24', temperature: 36.85, cervix: { opening: 0, firmness: 0 } },
+  { date: '2018-05-25', temperature: 36.95, cervix: { opening: 0, firmness: 0 } },
+  { date: '2018-05-26', temperature: 36.85, cervix: { opening: 0, firmness: 1 } },
+  { date: '2018-05-27', temperature: 36.8, cervix: { opening: 1, firmness: 0 } },
+  { date: '2018-05-28', temperature: 36.6, cervix: { opening: 1, firmness: 0 } },
+  { date: '2018-05-29', bleeding: 2 }
+].map(convertToSymptoFormat)
+
+export const cervixShift2DaysAfterTempShift = [
+  { date: '2018-04-05', bleeding: 3 },
+  { date: '2018-04-06', bleeding: 2 },
+  { date: '2018-04-07', bleeding: 2 },
+  { date: '2018-04-08', bleeding: 1 },
+  { date: '2018-04-09', temperature: 36.5 },
+  { date: '2018-04-10', temperature: 36.5, cervix: { opening: 1, firmness: 1 } },
+  { date: '2018-04-11', temperature: 36.55, cervix: { opening: 1, firmness: 1 } },
+  { date: '2018-04-12', temperature: 36.5, cervix: { opening: 1, firmness: 1 } },
+  { date: '2018-04-13', temperature: 36.35, cervix: { opening: 1, firmness: 1 } },
+  { date: '2018-04-14', temperature: 36.35, cervix: { opening: 1, firmness: 1 } },
+  { date: '2018-04-15', temperature: 36.6, cervix: { opening: 1, firmness: 1 } },
+  { date: '2018-04-16', temperature: 36.8, cervix: { opening: 1, firmness: 1 } },
+  { date: '2018-04-17', temperature: 36.8, cervix: { opening: 0, firmness: 0 } },
+  { date: '2018-04-18', temperature: 36.8, cervix: { opening: 0, firmness: 0 } },
+  { date: '2018-04-19', temperature: 36.85, cervix: { opening: 0, firmness: 0 } },
+  { date: '2018-04-20', temperature: 37.0, cervix: { opening: 0, firmness: 0 } },
+  { date: '2018-04-22', temperature: 36.9, cervix: { opening: 0, firmness: 0 } },
+  { date: '2018-04-23', temperature: 37.1, cervix: { opening: 0, firmness: 0 } },
+  { date: '2018-04-24', temperature: 36.75, cervix: { opening: 0, firmness: 0 } }
+].map(convertToSymptoFormat)
+
+export const noOvulationDetected = [
+  { date: '2018-03-08', bleeding: 3 },
+  { date: '2018-03-09', bleeding: 3 },
+  { date: '2018-03-10', bleeding: 3 },
+  { date: '2018-03-11', bleeding: 3 },
+  { date: '2018-03-12', temperature: 36.3, cervix: { opening: 0, firmness: 0 } },
+  { date: '2018-03-13', temperature: 36.5, cervix: { opening: 1, firmness: 1 } },
+  { date: '2018-03-14', temperature: 36.45, cervix: { opening: 1, firmness: 1 } },
+  { date: '2018-03-15', temperature: 36.4, cervix: { opening: 1, firmness: 1 } },
+  { date: '2018-03-16', temperature: 36.2, cervix: { opening: 1, firmness: 1 } },
+  { date: '2018-03-17', temperature: 36.5, cervix: { opening: 1, firmness: 1 } },
+  { date: '2018-03-18', temperature: 36.6, cervix: { opening: 1, firmness: 1 } },
+  { date: '2018-03-19', temperature: 36.35, cervix: { opening: 1, firmness: 0 } },
+  { date: '2018-03-20', temperature: 36.8, cervix: { opening: 0, firmness: 0 } },
+  { date: '2018-03-21', temperature: 36.7, cervix: { opening: 0, firmness: 0 } },
+  { date: '2018-03-22', temperature: 36.7, cervix: { opening: 0, firmness: 1 } },
+  { date: '2018-03-23', temperature: 36.7, cervix: { opening: 0, firmness: 0 } }
+].map(convertToSymptoFormat)
+
+export const fiveDayCycle = [
+  { date: '2018-08-01', bleeding: 2 },
+  { date: '2018-08-03', bleeding: 3 }
+].map(convertToSymptoFormat)
diff --git a/test/sympto/cervix-temp.spec.js b/test/sympto/cervix-temp.spec.js
new file mode 100644
index 0000000..e2d8fa0
--- /dev/null
+++ b/test/sympto/cervix-temp.spec.js
@@ -0,0 +1,221 @@
+import chai from 'chai'
+import getSensiplanStatus from '../../lib/sympto'
+import {
+  cervixShiftAndFhmOnSameDay,
+  cycleWithFhmNoCervixShift,
+  cycleWithoutFhm,
+  longCycleWithoutAnyShifts,
+  tempShift3DaysAfterCervixShift,
+  cervixShift2DaysAfterTempShift,
+  noOvulationDetected,
+  fiveDayCycle
+} from './cervix-temp-fixtures'
+
+const expect = chai.expect
+
+describe('sympto', () => {
+  describe('combining temperature and cervix tracking', () => {
+    describe('with no previous higher temp measurement', () => {
+      it('with no temp or cervix shifts detects only peri-ovulatory', () => {
+        const status = getSensiplanStatus({
+          cycle: longCycleWithoutAnyShifts,
+          previousCycle: cycleWithoutFhm,
+          secondarySymptom: 'cervix'
+        })
+        expect(Object.keys(status.phases).length).to.eql(1)
+        expect(status).to.eql({
+          phases: {
+            periOvulatory: {
+              start: { date: '2018-07-01' },
+              cycleDays: longCycleWithoutAnyShifts
+            }
+          }
+        })
+      })
+      it('with temp but no cervix shift detects only peri-ovulatory', () => {
+        const status = getSensiplanStatus({
+          cycle: cycleWithFhmNoCervixShift,
+          previousCycle: cycleWithoutFhm,
+          secondarySymptom: 'cervix'
+        })
+        expect(Object.keys(status.phases).length).to.eql(1)
+        expect(status).to.eql({
+          phases: {
+            periOvulatory: {
+              start: { date: '2018-08-01' },
+              cycleDays: cycleWithFhmNoCervixShift
+            }
+          }
+        })
+      })
+      it('with temp and cervix shifts at the same day an no previous cycle detects only peri- and post-ovulatory phases', () => {
+        const status = getSensiplanStatus({
+          cycle: cervixShiftAndFhmOnSameDay,
+          secondarySymptom: 'cervix'
+        })
+        expect(Object.keys(status.phases).length).to.eql(2)
+        expect(status.temperatureShift.evaluationCompleteDay.date).to.eql('2018-08-15')
+        expect(status.cervixShift.evaluationCompleteDay.date).to.eql('2018-08-15')
+        expect(status.temperatureShift.rule).to.eql(0)
+        expect(status.phases.periOvulatory).to.eql({
+          start: { date: '2018-08-01' },
+          end: { date: '2018-08-15', time: '18:00' },
+          cycleDays: cervixShiftAndFhmOnSameDay
+            .filter(({date}) => date <= '2018-08-15')
+        })
+        expect(status.phases.postOvulatory).to.eql({
+          start: { date: '2018-08-15', time: '18:00' },
+          cycleDays: cervixShiftAndFhmOnSameDay
+            .filter(({date}) => date >= '2018-08-15')
+        })
+      })
+    })
+    describe('with previous higher temp measurement', () => {
+      it('with no shifts in 5-day long cycle detects only peri-ovulatory according to 5-day rule', () => {
+        const status = getSensiplanStatus({
+          cycle: fiveDayCycle,
+          previousCycle: cervixShiftAndFhmOnSameDay,
+          secondarySymptom: 'cervix'
+        })
+        expect(Object.keys(status.phases).length).to.eql(1)
+        expect(status.phases.preOvulatory).to.eql({
+          cycleDays: fiveDayCycle,
+          start: { date: '2018-08-01' },
+          end: { date: '2018-08-05' }
+        })
+      })
+      it('with no shifts in long cycle detects pre- and peri-ovulatory phase according to 5-day-rule', () => {
+        const status = getSensiplanStatus({
+          cycle: longCycleWithoutAnyShifts,
+          previousCycle: cervixShiftAndFhmOnSameDay,
+          secondarySymptom: 'cervix'
+        })
+
+        expect(Object.keys(status.phases).length).to.eql(2)
+        expect(status.phases.preOvulatory).to.eql({
+          cycleDays: longCycleWithoutAnyShifts
+            .filter(({date}) => date <= '2018-07-05'),
+          start: { date: '2018-07-01' },
+          end: { date: '2018-07-05' }
+        })
+        expect(status.phases.periOvulatory).to.eql({
+          cycleDays: longCycleWithoutAnyShifts
+            .filter(({date}) => date >= '2018-07-06'),
+          start: { date: '2018-07-06' }
+        })
+      })
+      it('with temperature and cervix evaluation end on same day detects all 3 phases', () => {
+        const status = getSensiplanStatus({
+          cycle: cervixShiftAndFhmOnSameDay,
+          previousCycle: cervixShiftAndFhmOnSameDay,
+          secondarySymptom: 'cervix'
+        })
+        expect(Object.keys(status.phases).length).to.eql(3)
+        expect(status.temperatureShift.evaluationCompleteDay.date).to.eql('2018-08-15')
+        expect(status.cervixShift.evaluationCompleteDay.date).to.eql('2018-08-15')
+
+        expect(status.phases.preOvulatory).to.eql({
+          start: { date: '2018-08-01' },
+          end: { date: '2018-08-05' },
+          cycleDays: cervixShiftAndFhmOnSameDay
+            .filter(({date}) => date <= '2018-08-05')
+        })
+        expect(status.phases.periOvulatory).to.eql({
+          start: { date: '2018-08-06' },
+          end: { date: '2018-08-15', time: '18:00' },
+          cycleDays: cervixShiftAndFhmOnSameDay
+            .filter(({date}) => {
+              return date > '2018-08-05' && date <= '2018-08-15'
+            })
+        })
+        expect(status.phases.postOvulatory).to.eql({
+          start: { date: '2018-08-15', time: '18:00' },
+          cycleDays: cervixShiftAndFhmOnSameDay
+            .filter(({date}) => date >= '2018-08-15')
+        })
+      })
+      it('with temperature shift 3 days after cervix shift detects all 3 phases', () => {
+        const status = getSensiplanStatus({
+          cycle: tempShift3DaysAfterCervixShift,
+          previousCycle: cervixShiftAndFhmOnSameDay,
+          secondarySymptom: 'cervix'
+        })
+        expect(Object.keys(status.phases).length).to.eql(3)
+        expect(status.cervixShift).to.be.an('object')
+        expect(status.temperatureShift).to.be.an('object')
+        expect(status.cervixShift.evaluationCompleteDay.date).to.eql('2018-05-18')
+        expect(status.temperatureShift.evaluationCompleteDay.date).to.eql('2018-05-21')
+
+        expect(status.phases.preOvulatory).to.eql({
+          start: { date: '2018-05-08' },
+          end: { date: '2018-05-12' },
+          cycleDays: tempShift3DaysAfterCervixShift
+            .filter(({date}) => date <= '2018-05-12')
+        })
+        expect(status.phases.periOvulatory).to.eql({
+          start: { date:'2018-05-13'},
+          end: { date: '2018-05-21', time: '18:00' },
+          cycleDays: tempShift3DaysAfterCervixShift
+            .filter(({date}) => {
+              return date >= '2018-05-13' && date <= '2018-05-21'
+            })
+        })
+        expect(status.phases.postOvulatory).to.eql({
+          start: { date: '2018-05-21', time: '18:00' },
+          cycleDays: tempShift3DaysAfterCervixShift
+            .filter(({date}) => date >= '2018-05-21')
+        })
+      })
+      it('with cervix shift 2 days after temperature shift detects all 3 phases', () => {
+        const status = getSensiplanStatus({
+          cycle: cervixShift2DaysAfterTempShift,
+          previousCycle: cervixShiftAndFhmOnSameDay,
+          secondarySymptom: 'cervix'
+        })
+        expect(Object.keys(status.phases).length).to.eql(3)
+        expect(status.temperatureShift.rule).to.eql(0)
+        expect(status.temperatureShift.evaluationCompleteDay.date).to.eql('2018-04-17')
+        expect(status.cervixShift.evaluationCompleteDay.date).to.eql('2018-04-19')
+
+        expect(status.phases.preOvulatory).to.eql({
+          cycleDays: cervixShift2DaysAfterTempShift
+            .filter(({date}) => date <= '2018-04-09'),
+          start: { date: '2018-04-05' },
+          end: { date: '2018-04-09' }
+        })
+        expect(status.phases.periOvulatory).to.eql({
+          cycleDays: cervixShift2DaysAfterTempShift
+            .filter(({date}) => {
+              return date >= '2018-04-10' && date <= '2018-04-19'
+            }),
+          start: { date: '2018-04-10' },
+          end: { date: '2018-04-19', time: '18:00' }
+        })
+        expect(status.phases.postOvulatory).to.eql({
+          cycleDays: cervixShift2DaysAfterTempShift
+            .filter(({date}) => date >= '2018-04-19'),
+          start: { date: '2018-04-19', time: '18:00' }
+        })
+      })
+      it('with no shifts no ovulation is found detects only pre and peri-ovulatory phase', () => {
+        const status = getSensiplanStatus({
+          cycle: noOvulationDetected,
+          previousCycle: cervixShiftAndFhmOnSameDay,
+          secondarySymptom: 'cervix'
+        })
+        expect(Object.keys(status.phases).length).to.eql(2)
+        expect(status.phases.preOvulatory).to.eql({
+          cycleDays: noOvulationDetected
+            .filter(({date}) => date <= '2018-03-12'),
+          start: { date: '2018-03-08' },
+          end: { date: '2018-03-12' }
+        })
+        expect(status.phases.periOvulatory).to.eql({
+          cycleDays: noOvulationDetected
+            .filter(({date}) => date > '2018-03-12'),
+          start: { date: '2018-03-13' }
+        })
+      })
+    })
+  })
+})
diff --git a/test/sympto/cervix.spec.js b/test/sympto/cervix.spec.js
new file mode 100644
index 0000000..f8bbc3e
--- /dev/null
+++ b/test/sympto/cervix.spec.js
@@ -0,0 +1,165 @@
+import chai from 'chai'
+import getCervixStatus from '../../lib/sympto/cervix'
+
+const expect = chai.expect
+
+function turnIntoCycleDayObject(value, fakeDate) {
+  const hardAndClosed = {
+    opening: 0,
+    firmness: 0
+  }
+  const hardAndOpen = {
+    opening: 1,
+    firmness: 0
+  }
+  const softAndClosed = {
+    opening: 0,
+    firmness: 1
+  }
+  const softAndOpen = {
+    opening: 1,
+    firmness: 1
+  }
+  const cervixStates = [hardAndClosed, hardAndOpen, softAndClosed, softAndOpen]
+  return {
+    date: fakeDate,
+    cervix: {
+      opening: cervixStates[value].opening,
+      firmness: cervixStates[value].firmness,
+      exclude: false
+    }
+  }
+}
+
+describe('sympto', () => {
+  describe('detects cervix shift', () => {
+    it('when shift happens at day 13 with consistent following days of infertile cervix until tempEvalEnd', () => {
+      const values = [0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 3, 0, 0, 0, 0, 0, 0, 0]
+        .map(turnIntoCycleDayObject)
+      const status = getCervixStatus(values, 16)
+      expect(status).to.eql({
+        detected: true,
+        cervixPeakBeforeShift: {
+          date: 10,
+          cervix: {
+            opening: 1,
+            firmness: 1,
+            exclude: false
+          }
+        },
+        evaluationCompleteDay: {
+          date: 13,
+          cervix: {
+            opening: 0,
+            firmness: 0,
+            exclude: false
+          }
+        }
+      })
+    })
+    it('right at the start of cycle days even if later shift happens again because tempEvalEnd happened before second potential shift', () => {
+      const values = [2, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0]
+        .map(turnIntoCycleDayObject)
+      const status = getCervixStatus(values, 5)
+      expect(status).to.eql({
+        detected: true,
+        cervixPeakBeforeShift: {
+          date: 0,
+          cervix: {
+            opening: 0,
+            firmness: 1,
+            exclude: false
+          },
+        },
+        evaluationCompleteDay: {
+          date: 3,
+          cervix: {
+            opening: 0,
+            firmness: 0,
+            exclude: false
+          }
+        }
+      })
+    })
+    it('at day 6 although right at the start of cycle days a potential shift happened but because tempEvalEnd happens after second shift', () => {
+      const values = [2, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0]
+        .map(turnIntoCycleDayObject)
+      const status = getCervixStatus(values, 10)
+      expect(status).to.eql({
+        detected: true,
+        cervixPeakBeforeShift: {
+          date: 6,
+          cervix: {
+            opening: 1,
+            firmness: 0,
+            exclude: false
+          },
+        },
+        evaluationCompleteDay: {
+          date: 9,
+          cervix: {
+            opening: 0,
+            firmness: 0,
+            exclude: false
+          }
+        }
+      })
+    })
+    it('when the cervix shift is happening after tempEvalEnd', () => {
+      const values = [1,1,1,1,1,2,3,3,3,3,1,1,1,1,0,0,0,0,0,0,0]
+        .map(turnIntoCycleDayObject)
+      const status = getCervixStatus(values, 10)
+      expect(status).to.eql({
+        detected: true,
+        cervixPeakBeforeShift: {
+          date: 13,
+          cervix: {
+            opening: 1,
+            firmness: 0,
+            exclude: false
+          }
+        },
+        evaluationCompleteDay: {
+          date: 16,
+          cervix: {
+            opening: 0,
+            firmness: 0,
+            exclude: false
+          }
+        }
+      })
+    })
+  })
+
+  describe('detects no cervix shift', () => {
+    it('if there are less than 3 days closed and hard cervix', () => {
+      const values = [0, 0, 0, 1, 1, 1, 2, 0, 3, 3, 3, 1, 1, 1, 0, 0, 2, 0]
+        .map(turnIntoCycleDayObject)
+      const status = getCervixStatus(values, 15)
+      expect(status).to.eql({ detected: false })
+    })
+    it('if cycleDays have not enough cervix values to detect valid cervix shift', () => {
+      const values = [2,0,0]
+        .map(turnIntoCycleDayObject)
+      const status = getCervixStatus(values, 17)
+      expect(status).to.eql({ detected: false })
+    })
+    it('if no days indicate fertile cervix which could be cervix peak', () => {
+      const values = [1, 3, 2, 1, 3, 2, 1, 3, 2, 1, 3, 2, 1, 3, 2, 1]
+        .map(turnIntoCycleDayObject)
+      const status = getCervixStatus(values, 12)
+      expect(status).to.eql({ detected: false })
+    })
+    it('if all days indicate infertile cervix values', () => {
+      const values = [0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0]
+        .map(turnIntoCycleDayObject)
+      const status = getCervixStatus(values, 9)
+      expect(status).to.eql({ detected: false })
+    })
+    it('if there are no cervix values', () => {
+      const values = [].map(turnIntoCycleDayObject)
+      const status = getCervixStatus(values, 15)
+      expect(status).to.eql({ detected: false })
+    })
+  })
+})
diff --git a/test/sympto/index.spec.js b/test/sympto/index.spec.js
deleted file mode 100644
index 8f1df47..0000000
--- a/test/sympto/index.spec.js
+++ /dev/null
@@ -1,660 +0,0 @@
-import chai from 'chai'
-import getSensiplanStatus from '../../lib/sympto'
-import { AssertionError } from 'assert'
-import {
-  cycleWithoutFhm,
-  longAndComplicatedCycle,
-  cycleWithTempAndNoMucusShift,
-  cycleWithFhm,
-  cycleWithoutAnyShifts,
-  fiveDayCycle,
-  cycleWithEarlyMucus,
-  cycleWithMucusOnFirstDay,
-  mucusPeakAndFhmOnSameDay,
-  fhmTwoDaysBeforeMucusPeak,
-  fhm5DaysAfterMucusPeak,
-  mucusPeak5DaysAfterFhm,
-  mucusPeakTwoDaysBeforeFhm,
-  fhmOnDay12,
-  fhmOnDay15,
-  mucusPeakSlightlyBeforeTempShift,
-  highestMucusQualityAfterEndOfEval
-} from './fixtures'
-
-const expect = chai.expect
-
-describe('sympto', () => {
-  describe('with no previous higher measurement', () => {
-    it('with no shifts detects only peri-ovulatory', function () {
-      const status = getSensiplanStatus({
-        cycle: cycleWithoutAnyShifts,
-        previousCycle: cycleWithoutFhm
-      })
-
-      expect(status).to.eql({
-
-        phases: {
-          periOvulatory: {
-            start: { date: '2018-06-01' },
-            cycleDays: cycleWithoutAnyShifts
-          }
-        },
-      })
-    })
-
-    it('with shifts detects only peri-ovulatory and post-ovulatory', () => {
-      const status = getSensiplanStatus({
-        cycle: longAndComplicatedCycle,
-        previousCycle: cycleWithoutFhm
-      })
-
-      expect(status.temperatureShift).to.be.an('object')
-      expect(status.mucusShift).to.be.an('object')
-
-      expect(Object.keys(status.phases).length).to.eql(2)
-      expect(status.phases.periOvulatory).to.eql({
-        start: { date: '2018-06-01' },
-        end: { date: '2018-06-21', time: '18:00' },
-        cycleDays: longAndComplicatedCycle
-          .filter(({date}) => date <= '2018-06-21')
-      })
-      expect(status.phases.postOvulatory).to.eql({
-        start: {
-          date: '2018-06-21',
-          time: '18:00'
-        },
-        cycleDays: longAndComplicatedCycle
-          .filter(({date}) => date >= '2018-06-21')
-      })
-    })
-  })
-  describe('with previous higher measurement', () => {
-    describe('with no shifts detects pre-ovulatory phase', function () {
-      it('according to 5-day-rule', function () {
-        const status = getSensiplanStatus({
-          cycle: fiveDayCycle,
-          previousCycle: cycleWithFhm
-        })
-
-        expect(Object.keys(status.phases).length).to.eql(1)
-
-        expect(status.phases.preOvulatory).to.eql({
-          cycleDays: fiveDayCycle,
-          start: { date: '2018-06-01' },
-          end: { date: '2018-06-05' }
-        })
-      })
-
-    })
-    describe('with no shifts detects pre- and peri-ovulatory phase', () => {
-      it('according to 5-day-rule', function () {
-        const status = getSensiplanStatus({
-          cycle: cycleWithTempAndNoMucusShift,
-          previousCycle: cycleWithFhm
-        })
-
-        expect(Object.keys(status.phases).length).to.eql(2)
-
-        expect(status.phases.preOvulatory).to.eql({
-          cycleDays: cycleWithTempAndNoMucusShift
-            .filter(({date}) => date <= '2018-06-05'),
-          start: { date: '2018-06-01' },
-          end: { date: '2018-06-05' }
-        })
-        expect(status.phases.periOvulatory).to.eql({
-          cycleDays: cycleWithTempAndNoMucusShift
-            .filter(({date}) => date > '2018-06-05'),
-          start: { date: '2018-06-06' }
-        })
-      })
-      it('according to 5-day-rule with shortened pre-phase', function () {
-        const status = getSensiplanStatus({
-          cycle: cycleWithEarlyMucus,
-          previousCycle: cycleWithFhm
-        })
-
-        expect(Object.keys(status.phases).length).to.eql(2)
-
-        expect(status.phases.preOvulatory).to.eql({
-          cycleDays: [cycleWithEarlyMucus[0]],
-          start: { date: '2018-06-01' },
-          end: { date: '2018-06-01' }
-        })
-        expect(status.phases.periOvulatory).to.eql({
-          cycleDays: cycleWithEarlyMucus.slice(1),
-          start: { date: '2018-06-02' }
-        })
-      })
-    })
-    describe('with shifts detects pre- and peri-ovulatory phase', function () {
-      it('according to 5-day-rule', function () {
-        const status = getSensiplanStatus({
-          cycle: longAndComplicatedCycle,
-          previousCycle: cycleWithFhm
-        })
-
-        expect(Object.keys(status.phases).length).to.eql(3)
-
-        expect(status.phases.preOvulatory).to.eql({
-          cycleDays: longAndComplicatedCycle
-            .filter(({date}) => date <= '2018-06-05'),
-          start: { date: '2018-06-01' },
-          end: { date: '2018-06-05' }
-        })
-        expect(status.phases.periOvulatory).to.eql({
-          cycleDays: longAndComplicatedCycle
-            .filter(({date}) => date > '2018-06-05' && date <= '2018-06-21'),
-          start: { date: '2018-06-06' },
-          end: { date: '2018-06-21', time: '18:00'}
-        })
-        expect(status.phases.postOvulatory).to.eql({
-          cycleDays: longAndComplicatedCycle
-            .filter(({date}) => date >= '2018-06-21'),
-          start: { date: '2018-06-21', time: '18:00'}
-        })
-      })
-
-    })
-  })
-
-  describe('combining first higher measurment and mucus peak', () => {
-    it('with fhM + mucus peak on same day finds start of postovu phase', () => {
-      const status = getSensiplanStatus({
-        cycle: mucusPeakAndFhmOnSameDay,
-        previousCycle: cycleWithFhm
-      })
-
-      expect(status.temperatureShift).to.be.an('object')
-      expect(status.mucusShift).to.be.an('object')
-
-      expect(Object.keys(status.phases).length).to.eql(3)
-      expect(status.phases.preOvulatory).to.eql({
-        start: { date: '2018-06-01' },
-        end: { date: '2018-06-05' },
-        cycleDays: mucusPeakAndFhmOnSameDay
-          .filter(({date}) => date <= '2018-06-05')
-      })
-      expect(status.phases.periOvulatory).to.eql({
-        start: { date: '2018-06-06' },
-        end: { date: '2018-06-21', time: '18:00' },
-        cycleDays: mucusPeakAndFhmOnSameDay
-          .filter(({date}) => {
-            return date > '2018-06-05' && date <= '2018-06-21'
-          })
-      })
-      expect(status.phases.postOvulatory).to.eql({
-        start: {
-          date: '2018-06-21',
-          time: '18:00'
-        },
-        cycleDays: mucusPeakAndFhmOnSameDay
-          .filter(({date}) => date >= '2018-06-21')
-      })
-    })
-
-    it('with fhM 2 days before mucus peak waits for end of mucus eval', () => {
-      const status = getSensiplanStatus({
-        cycle: fhmTwoDaysBeforeMucusPeak,
-        previousCycle: cycleWithFhm
-      })
-
-      expect(status.temperatureShift).to.be.an('object')
-      expect(status.mucusShift).to.be.an('object')
-
-      expect(Object.keys(status.phases).length).to.eql(3)
-      expect(status.phases.preOvulatory).to.eql({
-        start: { date: '2018-06-01' },
-        end: { date: '2018-06-05' },
-        cycleDays: fhmTwoDaysBeforeMucusPeak
-          .filter(({date}) => date <= '2018-06-05')
-      })
-      expect(status.phases.periOvulatory).to.eql({
-        start: { date: '2018-06-06' },
-        end: { date: '2018-06-26', time: '18:00' },
-        cycleDays: fhmTwoDaysBeforeMucusPeak
-          .filter(({date}) => {
-            return date > '2018-06-05' && date <= '2018-06-26'
-          })
-      })
-      expect(status.phases.postOvulatory).to.eql({
-        start: {
-          date: '2018-06-26',
-          time: '18:00'
-        },
-        cycleDays: fhmTwoDaysBeforeMucusPeak
-          .filter(({date}) => date >= '2018-06-26')
-      })
-    })
-
-    it('another example for mucus peak before temp shift', () => {
-      const status = getSensiplanStatus({
-        cycle: mucusPeakSlightlyBeforeTempShift,
-        previousCycle: cycleWithFhm
-      })
-
-      expect(status.temperatureShift).to.be.an('object')
-      expect(status.mucusShift).to.be.an('object')
-
-      expect(Object.keys(status.phases).length).to.eql(3)
-      expect(status.phases.preOvulatory).to.eql({
-        start: { date: '2018-06-01' },
-        end: { date: '2018-06-05' },
-        cycleDays: mucusPeakSlightlyBeforeTempShift
-          .filter(({date}) => date <= '2018-06-05')
-      })
-      expect(status.phases.periOvulatory).to.eql({
-        start: { date: '2018-06-06' },
-        end: { date: '2018-06-17', time: '18:00' },
-        cycleDays: mucusPeakSlightlyBeforeTempShift
-          .filter(({date}) => {
-            return date > '2018-06-05' && date <= '2018-06-17'
-          })
-      })
-      expect(status.phases.postOvulatory).to.eql({
-        start: {
-          date: '2018-06-17',
-          time: '18:00'
-        },
-        cycleDays: mucusPeakSlightlyBeforeTempShift
-          .filter(({date}) => date >= '2018-06-17')
-      })
-    })
-
-    it('with another mucus peak 5 days after fHM ignores it', () => {
-      const status = getSensiplanStatus({
-        cycle: mucusPeak5DaysAfterFhm,
-        previousCycle: cycleWithFhm
-      })
-
-      expect(status.temperatureShift).to.be.an('object')
-      expect(status.mucusShift).to.be.an('object')
-
-      expect(Object.keys(status.phases).length).to.eql(3)
-      expect(status.phases.preOvulatory).to.eql({
-        start: { date: '2018-06-01' },
-        end: { date: '2018-06-01' },
-        cycleDays: mucusPeak5DaysAfterFhm
-          .filter(({date}) => date <= '2018-06-01')
-      })
-      expect(status.phases.periOvulatory).to.eql({
-        start: { date: '2018-06-02' },
-        end: { date: '2018-06-22', time: '18:00' },
-        cycleDays: mucusPeak5DaysAfterFhm
-          .filter(({date}) => {
-            return date > '2018-06-01' && date <= '2018-06-22'
-          })
-      })
-      expect(status.phases.postOvulatory).to.eql({
-        start: {
-          date: '2018-06-22',
-          time: '18:00'
-        },
-        cycleDays: mucusPeak5DaysAfterFhm
-          .filter(({date}) => date >= '2018-06-22')
-      })
-    })
-
-    it('with mucus peak 2 days before fhM waits for end of temp eval', () => {
-      const status = getSensiplanStatus({
-        cycle:  mucusPeakTwoDaysBeforeFhm,
-        previousCycle: cycleWithFhm
-      })
-
-      expect(status.temperatureShift).to.be.an('object')
-      expect(status.mucusShift).to.be.an('object')
-
-      expect(Object.keys(status.phases).length).to.eql(3)
-      expect(status.phases.preOvulatory).to.eql({
-        start: { date: '2018-06-01' },
-        end: { date: '2018-06-04' },
-        cycleDays: mucusPeakTwoDaysBeforeFhm
-          .filter(({date}) => date <= '2018-06-04')
-      })
-      expect(status.phases.periOvulatory).to.eql({
-        start: { date: '2018-06-05' },
-        end: { date: '2018-07-03', time: '18:00' },
-        cycleDays: mucusPeakTwoDaysBeforeFhm
-          .filter(({date}) => {
-            return date > '2018-06-04' && date <= '2018-07-03'
-          })
-      })
-      expect(status.phases.postOvulatory).to.eql({
-        start: {
-          date: '2018-07-03',
-          time: '18:00'
-        },
-        cycleDays: mucusPeakTwoDaysBeforeFhm
-          .filter(({date}) => date >= '2018-07-03')
-      })
-    })
-
-    it('with mucus peak 5 days before fhM waits for end of temp eval', () => {
-      const status = getSensiplanStatus({
-        cycle:  fhm5DaysAfterMucusPeak,
-        previousCycle: cycleWithFhm
-      })
-
-      expect(status.temperatureShift).to.be.an('object')
-      expect(status.mucusShift).to.be.an('object')
-
-      expect(Object.keys(status.phases).length).to.eql(3)
-      expect(status.phases.preOvulatory).to.eql({
-        start: { date: '2018-06-01' },
-        end: { date: '2018-06-05' },
-        cycleDays: fhm5DaysAfterMucusPeak
-          .filter(({date}) => date <= '2018-06-05')
-      })
-      expect(status.phases.periOvulatory).to.eql({
-        start: { date: '2018-06-06' },
-        end: { date: '2018-06-21', time: '18:00' },
-        cycleDays: fhm5DaysAfterMucusPeak
-          .filter(({date}) => {
-            return date > '2018-06-05' && date <= '2018-06-21'
-          })
-      })
-      expect(status.phases.postOvulatory).to.eql({
-        start: {
-          date: '2018-06-21',
-          time: '18:00'
-        },
-        cycleDays: fhm5DaysAfterMucusPeak
-          .filter(({date}) => date >= '2018-06-21')
-      })
-    })
-
-    it('with highest quality after end of eval', () => {
-      const status = getSensiplanStatus({
-        cycle: highestMucusQualityAfterEndOfEval,
-        previousCycle: cycleWithFhm
-      })
-
-      expect(status.temperatureShift).to.be.an('object')
-      expect(status.mucusShift).to.be.an('object')
-
-      expect(Object.keys(status.phases).length).to.eql(3)
-      expect(status.phases.preOvulatory).to.eql({
-        start: { date: '2018-06-01' },
-        end: { date: '2018-06-05' },
-        cycleDays: highestMucusQualityAfterEndOfEval
-          .filter(({date}) => date <= '2018-06-05')
-      })
-      expect(status.phases.periOvulatory).to.eql({
-        start: { date: '2018-06-06' },
-        end: { date: '2018-06-17', time: '18:00' },
-        cycleDays: highestMucusQualityAfterEndOfEval
-          .filter(({date}) => {
-            return date > '2018-06-05' && date <= '2018-06-17'
-          })
-      })
-      expect(status.phases.postOvulatory).to.eql({
-        start: {
-          date: '2018-06-17',
-          time: '18:00'
-        },
-        cycleDays: highestMucusQualityAfterEndOfEval
-          .filter(({date}) => date >= '2018-06-17')
-      })
-    })
-  })
-
-  describe('applying the minus-8 rule', () => {
-    it('shortens the pre-ovu phase if there is a previous <13 fhm', () => {
-      const status = getSensiplanStatus({
-        cycle:  longAndComplicatedCycle,
-        previousCycle: fhmOnDay15,
-        earlierCycles: [fhmOnDay12, ...Array(10).fill(fhmOnDay15)]
-      })
-
-      expect(status.temperatureShift).to.be.an('object')
-      expect(status.mucusShift).to.be.an('object')
-
-      expect(Object.keys(status.phases).length).to.eql(3)
-      expect(status.phases.preOvulatory).to.eql({
-        start: { date: '2018-06-01' },
-        end: { date: '2018-06-04' },
-        cycleDays: longAndComplicatedCycle
-          .filter(({date}) => date <= '2018-06-04')
-      })
-      expect(status.phases.periOvulatory).to.eql({
-        start: { date: '2018-06-05' },
-        end: { date: '2018-06-21', time: '18:00' },
-        cycleDays: longAndComplicatedCycle
-          .filter(({date}) => {
-            return date > '2018-06-04' && date <= '2018-06-21'
-          })
-      })
-      expect(status.phases.postOvulatory).to.eql({
-        start: {
-          date: '2018-06-21',
-          time: '18:00'
-        },
-        cycleDays: longAndComplicatedCycle
-          .filter(({date}) => date >= '2018-06-21')
-      })
-    })
-    it('shortens pre-ovu phase with prev <13 fhm even with <12 cycles', () => {
-      const status = getSensiplanStatus({
-        cycle:  longAndComplicatedCycle,
-        previousCycle: fhmOnDay12,
-        earlierCycles: Array(10).fill(fhmOnDay12)
-      })
-
-      expect(status.temperatureShift).to.be.an('object')
-      expect(status.mucusShift).to.be.an('object')
-
-      expect(Object.keys(status.phases).length).to.eql(3)
-      expect(status.phases.preOvulatory).to.eql({
-        start: { date: '2018-06-01' },
-        end: { date: '2018-06-04' },
-        cycleDays: longAndComplicatedCycle
-          .filter(({date}) => date <= '2018-06-04')
-      })
-      expect(status.phases.periOvulatory).to.eql({
-        start: { date: '2018-06-05' },
-        end: { date: '2018-06-21', time: '18:00' },
-        cycleDays: longAndComplicatedCycle
-          .filter(({date}) => {
-            return date > '2018-06-04' && date <= '2018-06-21'
-          })
-      })
-      expect(status.phases.postOvulatory).to.eql({
-        start: {
-          date: '2018-06-21',
-          time: '18:00'
-        },
-        cycleDays: longAndComplicatedCycle
-          .filter(({date}) => date >= '2018-06-21')
-      })
-    })
-    it('shortens the pre-ovu phase if mucus occurs', () => {
-      const status = getSensiplanStatus({
-        cycle: cycleWithEarlyMucus,
-        previousCycle: fhmOnDay12,
-        earlierCycles: Array(10).fill(fhmOnDay12)
-      })
-
-
-      expect(Object.keys(status.phases).length).to.eql(2)
-      expect(status.phases.preOvulatory).to.eql({
-        start: { date: '2018-06-01' },
-        end: { date: '2018-06-01' },
-        cycleDays: cycleWithEarlyMucus
-          .filter(({date}) => date <= '2018-06-01')
-      })
-      expect(status.phases.periOvulatory).to.eql({
-        start: { date: '2018-06-02' },
-        cycleDays: cycleWithEarlyMucus
-          .filter(({date}) => {
-            return date > '2018-06-01'
-          })
-      })
-    })
-
-    it('shortens the pre-ovu phase if mucus occurs even on the first day', () => {
-      const status = getSensiplanStatus({
-        cycle: cycleWithMucusOnFirstDay,
-        previousCycle: fhmOnDay12,
-        earlierCycles: Array(10).fill(fhmOnDay12)
-      })
-
-
-      expect(Object.keys(status.phases).length).to.eql(1)
-
-      expect(status.phases.periOvulatory).to.eql({
-        start: { date: '2018-06-01' },
-        cycleDays: cycleWithMucusOnFirstDay
-      })
-    })
-
-    it('lengthens the pre-ovu phase if >= 12 cycles with fhm > 13', () => {
-      const status = getSensiplanStatus({
-        cycle: longAndComplicatedCycle,
-        previousCycle: fhmOnDay15,
-        earlierCycles: Array(11).fill(fhmOnDay15)
-      })
-
-
-      expect(Object.keys(status.phases).length).to.eql(3)
-      expect(status.phases.preOvulatory).to.eql({
-        start: { date: '2018-06-01' },
-        end: { date: '2018-06-07' },
-        cycleDays: longAndComplicatedCycle
-          .filter(({date}) => date <= '2018-06-07')
-      })
-      expect(status.phases.periOvulatory).to.eql({
-        start: { date: '2018-06-08' },
-        end: { date: '2018-06-21', time: '18:00' },
-        cycleDays: longAndComplicatedCycle
-          .filter(({date}) => {
-            return date > '2018-06-07' && date <= '2018-06-21'
-          })
-      })
-      expect(status.phases.postOvulatory).to.eql({
-        start: {
-          date: '2018-06-21',
-          time: '18:00'
-        },
-        cycleDays: longAndComplicatedCycle
-          .filter(({date}) => date >= '2018-06-21')
-      })
-    })
-
-    it('does not lengthen the pre-ovu phase if < 12 cycles', () => {
-      const status = getSensiplanStatus({
-        cycle: longAndComplicatedCycle,
-        previousCycle: fhmOnDay15,
-        earlierCycles: Array(10).fill(fhmOnDay15)
-      })
-
-
-      expect(Object.keys(status.phases).length).to.eql(3)
-      expect(status.phases.preOvulatory).to.eql({
-        start: { date: '2018-06-01' },
-        end: { date: '2018-06-05' },
-        cycleDays: longAndComplicatedCycle
-          .filter(({date}) => date <= '2018-06-05')
-      })
-      expect(status.phases.periOvulatory).to.eql({
-        start: { date: '2018-06-06' },
-        end: { date: '2018-06-21', time: '18:00' },
-        cycleDays: longAndComplicatedCycle
-          .filter(({date}) => {
-            return date > '2018-06-05' && date <= '2018-06-21'
-          })
-      })
-      expect(status.phases.postOvulatory).to.eql({
-        start: {
-          date: '2018-06-21',
-          time: '18:00'
-        },
-        cycleDays: longAndComplicatedCycle
-          .filter(({date}) => date >= '2018-06-21')
-      })
-    })
-
-    it('does not detect any pre-ovu phase if prev cycle had no fhm', () => {
-      const status = getSensiplanStatus({
-        cycle: longAndComplicatedCycle,
-        previousCycle: cycleWithoutFhm,
-        earlierCycles: [...Array(12).fill(fhmOnDay15)]
-      })
-
-
-      expect(Object.keys(status.phases).length).to.eql(2)
-      expect(status.phases.periOvulatory).to.eql({
-        start: { date: '2018-06-01' },
-        end: { date: '2018-06-21', time: '18:00' },
-        cycleDays: longAndComplicatedCycle
-          .filter(({date}) => {
-            return date >= '2018-06-01' && date <= '2018-06-21'
-          })
-      })
-      expect(status.phases.postOvulatory).to.eql({
-        start: {
-          date: '2018-06-21',
-          time: '18:00'
-        },
-        cycleDays: longAndComplicatedCycle
-          .filter(({date}) => date >= '2018-06-21')
-      })
-    })
-  })
-
-  describe('when args are wrong', () => {
-    it('throws when arg object is not in right format', () => {
-      const wrongObject = { hello: 'world' }
-      expect(() => getSensiplanStatus(wrongObject)).to.throw(AssertionError)
-    })
-    it('throws if cycle array is empty', () => {
-      expect(() => getSensiplanStatus({cycle: []})).to.throw(AssertionError)
-    })
-    it('throws if cycle days are not in right format', () => {
-      expect(() => getSensiplanStatus({
-        cycle: [{
-          hello: 'world',
-          bleeding: { value: 0 }
-        }],
-        earlierCycles: [[{
-          date: '1992-09-09',
-          bleeding: { value: 0 }
-        }]]
-      })).to.throw(AssertionError)
-      expect(() => getSensiplanStatus({
-        cycle: [{
-          date: '2018-04-13',
-          temperature: {value: '35'},
-          bleeding: { value: 0 }
-        }],
-        earlierCycles: [[{
-          date: '1992-09-09',
-          bleeding: { value: 0 }
-        }]]
-      })).to.throw(AssertionError)
-      expect(() => getSensiplanStatus({
-        cycle: [{
-          date: '09-14-2017',
-          bleeding: { value: 0 }
-        }],
-        earlierCycles: [[{
-          date: '1992-09-09',
-          bleeding: { value: 0 }
-        }]]
-      })).to.throw(AssertionError)
-    })
-    it('throws if first cycle day does not have bleeding value', () => {
-      expect(() => getSensiplanStatus({
-        cycle: [{
-          date: '2017-01-01',
-          bleeding: {
-            value: 'medium'
-          }
-        }],
-        earlierCycles: [[
-          {
-            date: '2017-09-23',
-          }
-        ]]
-      })).to.throw(AssertionError)
-    })
-  })
-})
\ No newline at end of file
diff --git a/test/sympto/fixtures.js b/test/sympto/mucus-temp-fixtures.js
similarity index 90%
rename from test/sympto/fixtures.js
rename to test/sympto/mucus-temp-fixtures.js
index 0bb4f9f..d6463c0 100644
--- a/test/sympto/fixtures.js
+++ b/test/sympto/mucus-temp-fixtures.js
@@ -1,9 +1,17 @@
-
 function convertToSymptoFormat(val) {
   const sympto = { date: val.date }
-  if (val.temperature) sympto.temperature = { value: val.temperature }
-  if (val.mucus) sympto.mucus = { value: val.mucus }
-  if (val.bleeding) sympto.bleeding = { value: val.bleeding }
+  if (val.temperature) sympto.temperature = {
+    value: val.temperature,
+    exclude: false
+  }
+  if (val.mucus) sympto.mucus = {
+    value: val.mucus,
+    exclude: false
+  }
+  if (val.bleeding) sympto.bleeding = {
+    value: val.bleeding,
+    exclude: false
+  }
   return sympto
 }
 
@@ -15,7 +23,7 @@ export const cycleWithFhm = [
   { date: '2018-06-06', temperature: 36.7, mucus: 0 },
   { date: '2018-06-13', temperature: 36.8, mucus: 4 },
   { date: '2018-06-15', temperature: 36.9, mucus: 2 },
-  { date: '2018-06-17', temperature: 36.9, mucus: 2 },
+  { date: '2018-06-16', temperature: 36.9, mucus: 2 },
   { date: '2018-06-17', temperature: 36.9, mucus: 2 },
   { date: '2018-06-18', temperature: 36.9, mucus: 2 }
 ].map(convertToSymptoFormat)
@@ -227,6 +235,31 @@ export const mucusPeak5DaysAfterFhm = [
   { date: '2018-07-02', temperature: 36.9, mucus: 1 }
 ].map(convertToSymptoFormat)
 
+export const highestMucusQualityAfterEndOfEval = [
+  { date: '2018-06-01', temperature: 36.6, bleeding: 2 },
+  { date: '2018-06-02', temperature: 36.65, mucus: 2 },
+  { date: '2018-06-04', temperature: 36.6 },
+  { date: '2018-06-05', temperature: 36.55 },
+  { date: '2018-06-06', temperature: 36.7, mucus: 0 },
+  { date: '2018-06-09', temperature: 36.5, mucus: 1 },
+  { date: '2018-06-10', temperature: 36.4, mucus: 2 },
+  { date: '2018-06-13', temperature: 36.45, mucus: 3 },
+  { date: '2018-06-14', temperature: 36.5, mucus: 3 },
+  { date: '2018-06-15', temperature: 36.55, mucus: 3 },
+  { date: '2018-06-16', temperature: 36.7, mucus: 3 },
+  { date: '2018-06-17', temperature: 36.65, mucus: 3 },
+  { date: '2018-06-18', temperature: 36.60, mucus: 2 },
+  { date: '2018-06-19', temperature: 36.8, mucus: 3 },
+  { date: '2018-06-20', temperature: 36.85, mucus: 3 },
+  { date: '2018-06-21', temperature: 36.8, mucus: 3 },
+  { date: '2018-06-22', temperature: 36.9, mucus: 1 },
+  { date: '2018-06-25', temperature: 36.9, mucus: 1 },
+  { date: '2018-06-26', temperature: 36.8, mucus: 1 },
+  { date: '2018-06-30', temperature: 36.9, mucus: 1 },
+  { date: '2018-07-01', temperature: 36.9, mucus: 4 },
+  { date: '2018-07-02', temperature: 36.9, mucus: 1 }
+].map(convertToSymptoFormat)
+
 export const fhm5DaysAfterMucusPeak = [
   { date: '2018-06-01', temperature: 36.6, bleeding: 2 },
   { date: '2018-06-02', temperature: 36.65 },
@@ -299,26 +332,3 @@ export const mucusPeakSlightlyBeforeTempShift = [
   { date: '2018-06-21', temperature: 36.8, mucus: 1},
   { date: '2018-06-22', temperature: 36.8, mucus: 1}
 ].map(convertToSymptoFormat)
-
-
-export const highestMucusQualityAfterEndOfEval = [
-  { date: '2018-06-01', temperature: 36.6, bleeding: 2 },
-  { date: '2018-06-02', temperature: 36.65 },
-  { date: '2018-06-04', temperature: 36.6 },
-  { date: '2018-06-07', temperature: 36.4, mucus: 1 },
-  { date: '2018-06-08', temperature: 36.35, mucus: 2},
-  { date: '2018-06-09', temperature: 36.4, mucus: 2},
-  { date: '2018-06-10', temperature: 36.45, mucus: 2},
-  { date: '2018-06-11', temperature: 36.4, mucus: 2},
-  { date: '2018-06-12', temperature: 36.45, mucus: 2},
-  { date: '2018-06-13', temperature: 36.45, mucus: 3},
-  { date: '2018-06-14', temperature: 36.55, mucus: 2},
-  { date: '2018-06-15', temperature: 36.6, mucus: 2},
-  { date: '2018-06-16', temperature: 36.6, mucus: 2},
-  { date: '2018-06-17', temperature: 36.55, mucus: 2},
-  { date: '2018-06-18', temperature: 36.6, mucus: 1},
-  { date: '2018-06-19', temperature: 36.7, mucus: 4},
-  { date: '2018-06-20', temperature: 36.75, mucus: 1},
-  { date: '2018-06-21', temperature: 36.8, mucus: 1},
-  { date: '2018-06-22', temperature: 36.8, mucus: 1}
-].map(convertToSymptoFormat)
\ No newline at end of file
diff --git a/test/sympto/mucus-temp.spec.js b/test/sympto/mucus-temp.spec.js
new file mode 100644
index 0000000..c2a2563
--- /dev/null
+++ b/test/sympto/mucus-temp.spec.js
@@ -0,0 +1,594 @@
+import chai from 'chai'
+import getSensiplanStatus from '../../lib/sympto'
+import { AssertionError } from 'assert'
+import {
+  cycleWithoutFhm,
+  longAndComplicatedCycle,
+  cycleWithTempAndNoMucusShift,
+  cycleWithFhm,
+  cycleWithoutAnyShifts,
+  fiveDayCycle,
+  cycleWithEarlyMucus,
+  cycleWithMucusOnFirstDay,
+  mucusPeakAndFhmOnSameDay,
+  fhmTwoDaysBeforeMucusPeak,
+  fhm5DaysAfterMucusPeak,
+  mucusPeak5DaysAfterFhm,
+  mucusPeakTwoDaysBeforeFhm,
+  fhmOnDay12,
+  fhmOnDay15,
+  mucusPeakSlightlyBeforeTempShift
+} from './mucus-temp-fixtures'
+
+const expect = chai.expect
+
+describe('sympto', () => {
+  describe('combining temperature and mucus tracking', () => {
+    describe('with no previous higher temp measurement', () => {
+      it('with no shifts detects only peri-ovulatory', () => {
+        const status = getSensiplanStatus({
+          cycle: cycleWithoutAnyShifts,
+          previousCycle: cycleWithoutFhm
+        })
+        expect(status.phases.periOvulatory).to.eql({
+          start: { date: '2018-06-01' },
+          cycleDays: cycleWithoutAnyShifts
+        })
+      })
+      it('with temp and mucus shifts detects only peri-ovulatory and post-ovulatory', () => {
+        const status = getSensiplanStatus({
+          cycle: longAndComplicatedCycle,
+          previousCycle: cycleWithoutFhm
+        })
+        expect(status.temperatureShift).to.be.an('object')
+        expect(status.mucusShift).to.be.an('object')
+        expect(Object.keys(status.phases).length).to.eql(2)
+        expect(status.phases.periOvulatory).to.eql({
+          start: { date: '2018-06-01' },
+          end: { date: '2018-06-21', time: '18:00' },
+          cycleDays: longAndComplicatedCycle
+            .filter(({date}) => date <= '2018-06-21')
+        })
+        expect(status.phases.postOvulatory).to.eql({
+          start: {
+            date: '2018-06-21',
+            time: '18:00'
+          },
+          cycleDays: longAndComplicatedCycle
+            .filter(({date}) => date >= '2018-06-21')
+        })
+
+      })
+    })
+    describe('with previous higher measurement', () => {
+      describe('with no shifts detects pre-ovulatory phase', () => {
+        it('according to 5-day-rule', () => {
+          const status = getSensiplanStatus({
+            cycle: fiveDayCycle,
+            previousCycle: cycleWithFhm
+          })
+          expect(Object.keys(status.phases).length).to.eql(1)
+          expect(status.phases.preOvulatory).to.eql({
+            cycleDays: fiveDayCycle,
+            start: { date: '2018-06-01' },
+            end: { date: '2018-06-05' }
+          })
+        })
+      })
+      describe('with no shifts detects pre- and peri-ovulatory phase', () => {
+        it('according to 5-day-rule', () => {
+          const status = getSensiplanStatus({
+            cycle: cycleWithTempAndNoMucusShift,
+            previousCycle: cycleWithFhm
+          })
+          expect(Object.keys(status.phases).length).to.eql(2)
+          expect(status.phases.preOvulatory).to.eql({
+            cycleDays: cycleWithTempAndNoMucusShift
+              .filter(({date}) => date <= '2018-06-05'),
+            start: { date: '2018-06-01' },
+            end: { date: '2018-06-05' }
+          })
+          expect(status.phases.periOvulatory).to.eql({
+            cycleDays: cycleWithTempAndNoMucusShift
+              .filter(({date}) => date > '2018-06-05'),
+            start: { date: '2018-06-06' }
+          })
+        })
+        it('according to 5-day-rule with shortened pre-phase', () => {
+          const status = getSensiplanStatus({
+            cycle: cycleWithEarlyMucus,
+            previousCycle: cycleWithFhm
+          })
+          expect(Object.keys(status.phases).length).to.eql(2)
+          expect(status.phases.preOvulatory).to.eql({
+            cycleDays: [cycleWithEarlyMucus[0]],
+            start: { date: '2018-06-01' },
+            end: { date: '2018-06-01' }
+          })
+          expect(status.phases.periOvulatory).to.eql({
+            cycleDays: cycleWithEarlyMucus.slice(1),
+            start: { date: '2018-06-02' }
+          })
+        })
+      })
+      describe('with shifts detects pre- and peri-ovulatory phase', () => {
+        it('according to 5-day-rule', () => {
+          const status = getSensiplanStatus({
+            cycle: longAndComplicatedCycle,
+            previousCycle: cycleWithFhm
+          })
+          expect(Object.keys(status.phases).length).to.eql(3)
+          expect(status.phases.preOvulatory).to.eql({
+            cycleDays: longAndComplicatedCycle
+              .filter(({date}) => date <= '2018-06-05'),
+            start: { date: '2018-06-01' },
+            end: { date: '2018-06-05' }
+          })
+          expect(status.phases.periOvulatory).to.eql({
+            cycleDays: longAndComplicatedCycle
+              .filter(({date}) => date > '2018-06-05' && date <= '2018-06-21'),
+            start: { date: '2018-06-06' },
+            end: { date: '2018-06-21', time: '18:00'}
+          })
+          expect(status.phases.postOvulatory).to.eql({
+            cycleDays: longAndComplicatedCycle
+              .filter(({date}) => date >= '2018-06-21'),
+            start: { date: '2018-06-21', time: '18:00'}
+          })
+        })
+      })
+    })
+    describe('combining first higher measurment and mucus peak', () => {
+      it('with fhM + mucus peak on same day finds start of postovu phase', () => {
+        const status = getSensiplanStatus({
+          cycle: mucusPeakAndFhmOnSameDay,
+          previousCycle: cycleWithFhm
+        })
+
+        expect(status.temperatureShift).to.be.an('object')
+        expect(status.mucusShift).to.be.an('object')
+
+        expect(Object.keys(status.phases).length).to.eql(3)
+        expect(status.phases.preOvulatory).to.eql({
+          start: { date: '2018-06-01' },
+          end: { date: '2018-06-05' },
+          cycleDays: mucusPeakAndFhmOnSameDay
+            .filter(({date}) => date <= '2018-06-05')
+        })
+        expect(status.phases.periOvulatory).to.eql({
+          start: { date: '2018-06-06' },
+          end: { date: '2018-06-21', time: '18:00' },
+          cycleDays: mucusPeakAndFhmOnSameDay
+            .filter(({date}) => {
+              return date > '2018-06-05' && date <= '2018-06-21'
+            })
+        })
+        expect(status.phases.postOvulatory).to.eql({
+          start: {
+            date: '2018-06-21',
+            time: '18:00'
+          },
+          cycleDays: mucusPeakAndFhmOnSameDay
+            .filter(({date}) => date >= '2018-06-21')
+        })
+      })
+      it('with fhM 2 days before mucus peak waits for end of mucus eval', () => {
+        const status = getSensiplanStatus({
+          cycle: fhmTwoDaysBeforeMucusPeak,
+          previousCycle: cycleWithFhm
+        })
+
+        expect(status.temperatureShift).to.be.an('object')
+        expect(status.mucusShift).to.be.an('object')
+
+        expect(Object.keys(status.phases).length).to.eql(3)
+        expect(status.phases.preOvulatory).to.eql({
+          start: { date: '2018-06-01' },
+          end: { date: '2018-06-05' },
+          cycleDays: fhmTwoDaysBeforeMucusPeak
+            .filter(({date}) => date <= '2018-06-05')
+        })
+        expect(status.phases.periOvulatory).to.eql({
+          start: { date: '2018-06-06' },
+          end: { date: '2018-06-26', time: '18:00' },
+          cycleDays: fhmTwoDaysBeforeMucusPeak
+            .filter(({date}) => {
+              return date > '2018-06-05' && date <= '2018-06-26'
+            })
+        })
+        expect(status.phases.postOvulatory).to.eql({
+          start: {
+            date: '2018-06-26',
+            time: '18:00'
+          },
+          cycleDays: fhmTwoDaysBeforeMucusPeak
+            .filter(({date}) => date >= '2018-06-26')
+        })
+      })
+      it('another example for mucus peak before temp shift', () => {
+        const status = getSensiplanStatus({
+          cycle: mucusPeakSlightlyBeforeTempShift,
+          previousCycle: cycleWithFhm
+        })
+
+        expect(status.temperatureShift).to.be.an('object')
+        expect(status.mucusShift).to.be.an('object')
+
+        expect(Object.keys(status.phases).length).to.eql(3)
+        expect(status.phases.preOvulatory).to.eql({
+          start: { date: '2018-06-01' },
+          end: { date: '2018-06-05' },
+          cycleDays: mucusPeakSlightlyBeforeTempShift
+            .filter(({date}) => date <= '2018-06-05')
+        })
+        expect(status.phases.periOvulatory).to.eql({
+          start: { date: '2018-06-06' },
+          end: { date: '2018-06-17', time: '18:00' },
+          cycleDays: mucusPeakSlightlyBeforeTempShift
+            .filter(({date}) => {
+              return date > '2018-06-05' && date <= '2018-06-17'
+            })
+        })
+        expect(status.phases.postOvulatory).to.eql({
+          start: {
+            date: '2018-06-17',
+            time: '18:00'
+          },
+          cycleDays: mucusPeakSlightlyBeforeTempShift
+            .filter(({date}) => date >= '2018-06-17')
+        })
+      })
+      it('with another mucus peak 5 days after fHM ignores it', () => {
+        const status = getSensiplanStatus({
+          cycle: mucusPeak5DaysAfterFhm,
+          previousCycle: cycleWithFhm
+        })
+        expect(status.temperatureShift).to.be.an('object')
+        expect(status.mucusShift).to.be.an('object')
+        expect(Object.keys(status.phases).length).to.eql(3)
+        expect(status.phases.preOvulatory).to.eql({
+          start: { date: '2018-06-01' },
+          end: { date: '2018-06-01' },
+          cycleDays: mucusPeak5DaysAfterFhm
+            .filter(({date}) => date <= '2018-06-01')
+        })
+        expect(status.phases.periOvulatory).to.eql({
+          start: { date: '2018-06-02' },
+          end: { date: '2018-06-22', time: '18:00' },
+          cycleDays: mucusPeak5DaysAfterFhm
+            .filter(({date}) => {
+              return date > '2018-06-01' && date <= '2018-06-22'
+            })
+        })
+        expect(status.phases.postOvulatory).to.eql({
+          start: {
+            date: '2018-06-22',
+            time: '18:00'
+          },
+          cycleDays: mucusPeak5DaysAfterFhm
+            .filter(({date}) => date >= '2018-06-22')
+        })
+      })
+      it('with mucus peak 2 days before fhM waits for end of temp eval', () => {
+        const status = getSensiplanStatus({
+          cycle:  mucusPeakTwoDaysBeforeFhm,
+          previousCycle: cycleWithFhm
+        })
+        expect(status.temperatureShift).to.be.an('object')
+        expect(status.mucusShift).to.be.an('object')
+
+        expect(Object.keys(status.phases).length).to.eql(3)
+        expect(status.phases.preOvulatory).to.eql({
+          start: { date: '2018-06-01' },
+          end: { date: '2018-06-04' },
+          cycleDays: mucusPeakTwoDaysBeforeFhm
+            .filter(({date}) => date <= '2018-06-04')
+        })
+        expect(status.phases.periOvulatory).to.eql({
+          start: { date: '2018-06-05' },
+          end: { date: '2018-07-03', time: '18:00' },
+          cycleDays: mucusPeakTwoDaysBeforeFhm
+            .filter(({date}) => {
+              return date > '2018-06-04' && date <= '2018-07-03'
+            })
+        })
+        expect(status.phases.postOvulatory).to.eql({
+          start: {
+            date: '2018-07-03',
+            time: '18:00'
+          },
+          cycleDays: mucusPeakTwoDaysBeforeFhm
+            .filter(({date}) => date >= '2018-07-03')
+        })
+      })
+      it('with mucus peak 5 days before fhM waits for end of temp eval', () => {
+        const status = getSensiplanStatus({
+          cycle:  fhm5DaysAfterMucusPeak,
+          previousCycle: cycleWithFhm
+        })
+
+        expect(status.temperatureShift).to.be.an('object')
+        expect(status.mucusShift).to.be.an('object')
+
+        expect(Object.keys(status.phases).length).to.eql(3)
+        expect(status.phases.preOvulatory).to.eql({
+          start: { date: '2018-06-01' },
+          end: { date: '2018-06-05' },
+          cycleDays: fhm5DaysAfterMucusPeak
+            .filter(({date}) => date <= '2018-06-05')
+        })
+        expect(status.phases.periOvulatory).to.eql({
+          start: { date: '2018-06-06' },
+          end: { date: '2018-06-21', time: '18:00' },
+          cycleDays: fhm5DaysAfterMucusPeak
+            .filter(({date}) => {
+              return date > '2018-06-05' && date <= '2018-06-21'
+            })
+        })
+        expect(status.phases.postOvulatory).to.eql({
+          start: {
+            date: '2018-06-21',
+            time: '18:00'
+          },
+          cycleDays: fhm5DaysAfterMucusPeak
+            .filter(({date}) => date >= '2018-06-21')
+        })
+      })
+    })
+    describe('applying the minus-8 rule', () => {
+      it('shortens the pre-ovu phase if there is a previous <13 fhm', () => {
+        const status = getSensiplanStatus({
+          cycle:  longAndComplicatedCycle,
+          previousCycle: fhmOnDay15,
+          earlierCycles: [fhmOnDay12, ...Array(10).fill(fhmOnDay15)]
+        })
+
+        expect(status.temperatureShift).to.be.an('object')
+        expect(status.mucusShift).to.be.an('object')
+
+        expect(Object.keys(status.phases).length).to.eql(3)
+        expect(status.phases.preOvulatory).to.eql({
+          start: { date: '2018-06-01' },
+          end: { date: '2018-06-04' },
+          cycleDays: longAndComplicatedCycle
+            .filter(({date}) => date <= '2018-06-04')
+        })
+        expect(status.phases.periOvulatory).to.eql({
+          start: { date: '2018-06-05' },
+          end: { date: '2018-06-21', time: '18:00' },
+          cycleDays: longAndComplicatedCycle
+            .filter(({date}) => {
+              return date > '2018-06-04' && date <= '2018-06-21'
+            })
+        })
+        expect(status.phases.postOvulatory).to.eql({
+          start: {
+            date: '2018-06-21',
+            time: '18:00'
+          },
+          cycleDays: longAndComplicatedCycle
+            .filter(({date}) => date >= '2018-06-21')
+        })
+      })
+      it('shortens pre-ovu phase with prev <13 fhm even with <12 cycles', () => {
+        const status = getSensiplanStatus({
+          cycle:  longAndComplicatedCycle,
+          previousCycle: fhmOnDay12,
+          earlierCycles: Array(10).fill(fhmOnDay12)
+        })
+
+        expect(status.temperatureShift).to.be.an('object')
+        expect(status.mucusShift).to.be.an('object')
+
+        expect(Object.keys(status.phases).length).to.eql(3)
+        expect(status.phases.preOvulatory).to.eql({
+          start: { date: '2018-06-01' },
+          end: { date: '2018-06-04' },
+          cycleDays: longAndComplicatedCycle
+            .filter(({date}) => date <= '2018-06-04')
+        })
+        expect(status.phases.periOvulatory).to.eql({
+          start: { date: '2018-06-05' },
+          end: { date: '2018-06-21', time: '18:00' },
+          cycleDays: longAndComplicatedCycle
+            .filter(({date}) => {
+              return date > '2018-06-04' && date <= '2018-06-21'
+            })
+        })
+        expect(status.phases.postOvulatory).to.eql({
+          start: {
+            date: '2018-06-21',
+            time: '18:00'
+          },
+          cycleDays: longAndComplicatedCycle
+            .filter(({date}) => date >= '2018-06-21')
+        })
+      })
+      it('shortens the pre-ovu phase if mucus occurs', () => {
+        const status = getSensiplanStatus({
+          cycle: cycleWithEarlyMucus,
+          previousCycle: fhmOnDay12,
+          earlierCycles: Array(10).fill(fhmOnDay12)
+        })
+
+
+        expect(Object.keys(status.phases).length).to.eql(2)
+        expect(status.phases.preOvulatory).to.eql({
+          start: { date: '2018-06-01' },
+          end: { date: '2018-06-01' },
+          cycleDays: cycleWithEarlyMucus
+            .filter(({date}) => date <= '2018-06-01')
+        })
+        expect(status.phases.periOvulatory).to.eql({
+          start: { date: '2018-06-02' },
+          cycleDays: cycleWithEarlyMucus
+            .filter(({date}) => {
+              return date > '2018-06-01'
+            })
+        })
+      })
+      it('shortens the pre-ovu phase if mucus occurs even on the first day', () => {
+        const status = getSensiplanStatus({
+          cycle: cycleWithMucusOnFirstDay,
+          previousCycle: fhmOnDay12,
+          earlierCycles: Array(10).fill(fhmOnDay12)
+        })
+
+
+        expect(Object.keys(status.phases).length).to.eql(1)
+
+        expect(status.phases.periOvulatory).to.eql({
+          start: { date: '2018-06-01' },
+          cycleDays: cycleWithMucusOnFirstDay
+        })
+      })
+      it('lengthens the pre-ovu phase if >= 12 cycles with fhm > 13', () => {
+        const status = getSensiplanStatus({
+          cycle: longAndComplicatedCycle,
+          previousCycle: fhmOnDay15,
+          earlierCycles: Array(11).fill(fhmOnDay15)
+        })
+
+
+        expect(Object.keys(status.phases).length).to.eql(3)
+        expect(status.phases.preOvulatory).to.eql({
+          start: { date: '2018-06-01' },
+          end: { date: '2018-06-07' },
+          cycleDays: longAndComplicatedCycle
+            .filter(({date}) => date <= '2018-06-07')
+        })
+        expect(status.phases.periOvulatory).to.eql({
+          start: { date: '2018-06-08' },
+          end: { date: '2018-06-21', time: '18:00' },
+          cycleDays: longAndComplicatedCycle
+            .filter(({date}) => {
+              return date > '2018-06-07' && date <= '2018-06-21'
+            })
+        })
+        expect(status.phases.postOvulatory).to.eql({
+          start: {
+            date: '2018-06-21',
+            time: '18:00'
+          },
+          cycleDays: longAndComplicatedCycle
+            .filter(({date}) => date >= '2018-06-21')
+        })
+      })
+      it('does not lengthen the pre-ovu phase if < 12 cycles', () => {
+        const status = getSensiplanStatus({
+          cycle: longAndComplicatedCycle,
+          previousCycle: fhmOnDay15,
+          earlierCycles: Array(10).fill(fhmOnDay15)
+        })
+
+
+        expect(Object.keys(status.phases).length).to.eql(3)
+        expect(status.phases.preOvulatory).to.eql({
+          start: { date: '2018-06-01' },
+          end: { date: '2018-06-05' },
+          cycleDays: longAndComplicatedCycle
+            .filter(({date}) => date <= '2018-06-05')
+        })
+        expect(status.phases.periOvulatory).to.eql({
+          start: { date: '2018-06-06' },
+          end: { date: '2018-06-21', time: '18:00' },
+          cycleDays: longAndComplicatedCycle
+            .filter(({date}) => {
+              return date > '2018-06-05' && date <= '2018-06-21'
+            })
+        })
+        expect(status.phases.postOvulatory).to.eql({
+          start: {
+            date: '2018-06-21',
+            time: '18:00'
+          },
+          cycleDays: longAndComplicatedCycle
+            .filter(({date}) => date >= '2018-06-21')
+        })
+      })
+      it('does not detect any pre-ovu phase if prev cycle had no fhm', () => {
+        const status = getSensiplanStatus({
+          cycle: longAndComplicatedCycle,
+          previousCycle: cycleWithoutFhm,
+          earlierCycles: [...Array(12).fill(fhmOnDay15)]
+        })
+
+
+        expect(Object.keys(status.phases).length).to.eql(2)
+        expect(status.phases.periOvulatory).to.eql({
+          start: { date: '2018-06-01' },
+          end: { date: '2018-06-21', time: '18:00' },
+          cycleDays: longAndComplicatedCycle
+            .filter(({date}) => {
+              return date >= '2018-06-01' && date <= '2018-06-21'
+            })
+        })
+        expect(status.phases.postOvulatory).to.eql({
+          start: {
+            date: '2018-06-21',
+            time: '18:00'
+          },
+          cycleDays: longAndComplicatedCycle
+            .filter(({date}) => date >= '2018-06-21')
+        })
+      })
+    })
+    describe('when args are wrong', () => {
+      it('throws when arg object is not in right format', () => {
+        const wrongObject = { hello: 'world' }
+        expect(() => getSensiplanStatus(wrongObject)).to.throw(AssertionError)
+      })
+      it('throws if cycle array is empty', () => {
+        expect(() => getSensiplanStatus({cycle: []})).to.throw(AssertionError)
+      })
+      it('throws if cycle days are not in right format', () => {
+        expect(() => getSensiplanStatus({
+          cycle: [{
+            hello: 'world',
+            bleeding: { value: 0 }
+          }],
+          earlierCycles: [[{
+            date: '1992-09-09',
+            bleeding: { value: 0 }
+          }]]
+        })).to.throw(AssertionError)
+        expect(() => getSensiplanStatus({
+          cycle: [{
+            date: '2018-04-13',
+            temperature: {value: '35'},
+            bleeding: { value: 0 }
+          }],
+          earlierCycles: [[{
+            date: '1992-09-09',
+            bleeding: { value: 0 }
+          }]]
+        })).to.throw(AssertionError)
+        expect(() => getSensiplanStatus({
+          cycle: [{
+            date: '09-14-2017',
+            bleeding: { value: 0 }
+          }],
+          earlierCycles: [[{
+            date: '1992-09-09',
+            bleeding: { value: 0 }
+          }]]
+        })).to.throw(AssertionError)
+      })
+      it('throws if first cycle day does not have bleeding value', () => {
+        expect(() => getSensiplanStatus({
+          cycle: [{
+            date: '2017-01-01',
+            bleeding: {
+              value: 'medium'
+            }
+          }],
+          earlierCycles: [[
+            {
+              date: '2017-09-23',
+            }
+          ]]
+        })).to.throw(AssertionError)
+      })
+    })
+  })
+})