NORDIC Natural Cycles Stand Alone Software Application User Manual

Natural Cycles is a software application for women 18 years and older to monitor their fertility. It can be used for contraception or conception purposes.

Contraindications

There are no known contraindications for using Natural Cycles. However, it may not be suitable if you have specific medical conditions or are currently on hormonal birth control.

Warnings

Natural Cycles is not 100% effective in preventing pregnancy. It is important to follow the app’s recommendations and use additional protection on red days to prevent pregnancy.

Instructions for Use

Indications for Use

Natural Cycles is a stand-alone software application, intended for women 18 years and older, to monitor their fertility. Natural Cycles can be used for preventing a pregnancy (contraception) or planning a pregnancy (conception).

Contraindications

There are no known contraindications for use of Natural Cycles.

Natural Cycles may not be right for you if

You have a medical condition where pregnancy would be associated with a significant risk to the mother or the fetus. Using Natural Cycles does not guarantee 100% that you will not get pregnant. If pregnancy presents a significant risk, you should talk to your doctor about the best contraceptive option for you.

You are currently taking hormonal birth control or undergoing hormonal treatment that inhibits ovulation. Natural Cycles will mainly provide red days if you do not ovulate. You can explore the app in Demo Mode until you discontinue your hormonal birth control or treatment.
You have irregular menstrual cycles (i.e. cycles with length less than 21 days or greater than 35 days). Predicting your fertility is more difficult in these circumstances, and the application will display an increased number of red days, which can reduce your satisfaction with Natural Cycles as a contraceptive method.

Warnings

No method of contraception is 100% eff ective. Natural Cycles does not guarantee that you cannot get pregnant, it only informs you whether and when you can become pregnant based on the information that you enter into the application.
Even with using the app perfectly, you can still have an unintended pregnancy. Natural Cycles is 93% eff ective under typical use, which means that 7 women out of 100 get pregnant during 1 year of use. With using the app perfectly, i.e. if you never have unprotected intercourse on red days, Natural Cycles is 98% eff ective, which means that 2 women out of 100 get pregnant during 1 year of use.

On red days, you must either abstain or use protection, such as condoms or another form of barrier protection, to prevent pregnancy. If you have not been using a non-hormonal method of contraception before, make sure to have a method on hand to use during red days.
Our data show that women transitioning to Natural Cycles from hormonal contraception have a higher risk of becoming pregnant due to generally not yet being accustomed to using other forms of protection, such as a condom or another form of barrier protection.

If you are discontinuing hormonal contraception, you may first experience a withdrawal bleed, which is much lighter than your true period. You will normally get your true period a few weeks later. Withdrawal bleeding should not be entered as “period”. If you are unsure if you are experiencing withdrawal bleeding or a period, please consult your doctor.
Natural Cycles does not protect against sexually transmitted infections (STIs). Use a condom to protect against STIs.

Always check your fertility status for the day. Be aware that fertility predictions for upcoming days are only predictions and may change in the future. If you are unsure of your fertility status and can’t access the app, abstain or use protection in the meantime.
If you are exploring the demo version of the app, this is for informational or instructional purposes only and does not display real data. Do not use the information displayed in Demo Mode for contraceptive purposes.

If you have taken the emergency contraceptive pill, you should indicate it in the app. You can then continue measuring as normal and the algorithm will take the additional hormones from the pill into account. Note that the bleeding you may experience a few days after taking emergency contraception is not the same as your regular period and should not be entered into the app. If your period is more than one week late after it normally would start you should take a pregnancy test.

Precautions

As a contraceptive, Natural Cycles may be less suitable for you if you have irregular menstrual cycles (i.e. cycles with length less than 21 days or greater than 35 days) and/or fluctuating temperatures as predicting fertility is more difficult in these circumstances. Natural Cycles’ eff ectiveness as a contraceptive is not aff ected by irregular cycles, but you will experience an increased number of red days, which can reduce your satisfaction with Natural Cycles. This can be the case:
- If you discontinue hormonal contraception. It can take several cycles after discontinuing hormonal contraception before becoming more regular again. You should expect more red days during these cycles and therefore expect to use protection or abstain more frequently.
- If you have medical conditions that lead to irregular cycles such as polycystic ovary syndrome (PCOS) or thyroid-related conditions.
- If you experience symptoms of menopause.
After giving birth, we recommend you start using Natural Cycles in your preferred mode when you get your period back. How long it may take to get your first period after delivery can vary significantly from person to person, and it is generally longer for breastfeeding mothers. If you wish to start using Natural Cycles sooner, you should expect to have only red days until your first ovulation is confirmed meaning you will need a barrier contraception or abstain from coital, sexual activity for that duration. For some breastfeeding mothers, their period may not come back for several months, but you are at risk of becoming pregnant even before your period comes back. Therefore, you should abstain from coital, sexual activity or use a barrier method or some other form of contraception during this time if you wish to prevent a new pregnancy.
When you start using Natural Cycles, it can take some time to get to know your unique cycle, resulting in an increased number of red days during your first 1-3 cycles. This is to ensure that the app is eff ective from the fi rst day of use, and once Natural Cycles has detected your ovulation you are likely to receive more green days. It is important to note that you can rely on the fertility status indicated by the app from the first day of use.
Always make sure to update your software app, so that you have the latest version. Using the latest version will help keep your app safe from cybersecurity threats and vulnerabilities. Your app is updated via your app store. Natural Cycles recommends that you set your smartphone to update the app automatically.
To ensure accurate data inputs to Natural Cycles, always use a thermometer or wearable that fulfils the specifications stated in the section ‘Checklist’.
Always follow the directions in the applicable sections ‘Natural Cycles and Oura Ring’, ‘Natural Cycles and Apple Watch’ or ‘Natural Cycles and Thermometer’ in order to increase the accuracy of ovulation detection.

Checklist

A Natural Cycles account

You can access Natural Cycles via your web browser, by visiting www.naturalcycles.com.
For access via the app, download the app on your Android, iPhone or iPad on Google Play or the App Store. Follow the registration steps to create your personal account. Make sure the device you use to access Natural Cycles is connected to the internet. Your Natural Cycles account is personal and should not be used by anyone except you.

A thermometer, an Oura Ring or an Apple Watch

To get started you will need an oral basal thermometer. Basal thermometers are more sensitive than regular fever thermometers. They measure temperature showing two decimals (e.g. 36.72°C/98.11°F) with an accuracy of +/- 0.10°C or +/-0.10°F.
You can alternatively use an Oura Ring (Gen2, Gen3, or Gen4) or an Apple Watch with temperature sensors (Series 8, Series 9, Series 10 or Ultra).

Ovulation tests (optional)

Ovulation (LH) tests are urine test strips which detect the surge of luteinizing hormone that occurs 1-2 days before ovulation. It is optional to use LH tests with Natural Cycles, but they can help to increase the accuracy of detecting ovulation and can, therefore, increase the number of green days you will see if you are preventing a pregnancy. Using LH tests will not aff ect the eff ectiveness of Natural Cycles as a contraceptive. If you are planning a pregnancy, we recommend using LH tests as they can help to find your most fertile days. You can purchase LH tests at shop.naturalcycles.com or from within the app itself.

Natural Cycles and Thermometer

How to measure

Follow the user manual provided with your basal body temperature thermometer. If the thermometer was provided to you by Natural Cycles (NC° Thermometer Gen1, Gen2, or Gen3), we recommend that you follow the steps below for your thermometer when measuring your temperature.
Note that for NC° Thermometer Gen2 and Gen3 you need to pair the thermometer with the app before first use to be able to sync your temperatures. Instructions on how to pair are provided in the thermometer’s instructions for use and in the Natural Cycles app.

How to measure with NC° Thermometer (Gen1)

Place the thermometer in your mouth and under your tongue, as far back as possible, next to the root of your tongue as depicted in the diagrams below.
Only press the power button once the thermometer is in your mouth and in place.

Try to keep still while measuring, close your mouth to keep any cool air out and breathe through your nose.
Wait until it beeps (approx. 30 seconds).
Once you have your reading, add the temperature into the app.

You can use the ‘Measuring Training’ and the ‘Measuring Guide’ in the app to check your measuring skills.

The thermometer will save your reading, so you can check your reading once again later. To do this press the “on” button once; the saved reading will appear for a few seconds before the temperature resets.

How to measure with NC° Thermometer (Gen2)

Press the power button on your Bluetooth thermometer NC° Thermometer (Gen2) and wait until you hear a beep and/or the backlight flashes. This is a signal from the thermometer that it’s ready to start the measurement.
Place the thermometer in your mouth and under your tongue, as far back as possible, next to the root of your tongue as depicted in the diagram above.
Try to keep still while measuring, close your mouth to keep any cool air out and breathe through your nose.

Wait until you hear a long beep and/or the backlight flash (approx. 30 seconds).
The temperature should appear automatically in the app. You can also choose to add the temperature manually or sync it later.

You can use the ‘Measuring Training’ and the ‘Measuring Guide’ in the app to check your measuring skills.
The thermometer will save your reading so you can check it later. To do this press the “bluetooth” button for at least 5 seconds; the saved reading will appear on the screen in the memory mode.

How to measure with NC° Thermometer (Gen3)

Press the power button and then place the thermometer in your mouth to begin measuring.
Place the probe under the tongue as near as possible to a heat pocket at the back of the mouth, as noted in the diagram above.

Hold the thermometer in place during the measurement; do not bite down on the thermometer. The mouth must remain closed to ensure accurate results. The reading should take approximately 40 seconds.
When the measurement is complete the thermometer will provide feedback. The feedback can be light and/or sound based on user settings. The fi nal temperature value will be displayed on the thermometer screen.
After a measurement is completed, simply press the power button to turn the thermometer off or the thermometer will shut off automatically. The temperature should appear automatically in the app. You can also choose to add the temperature manually or sync it later.

The thermometer will save your reading so you can check it later. To do this press the “history” button; the last temperature will appear on the screen in the history mode.

When to measure

Measure your temperature once a day, on as many days as possible, so that the algorithm can quickly get to know your unique cycle. Aim to measure at least 5 days a week. A tip to help you remember is to place your thermometer on top of your phone before going to bed.

Measure first thing in the morning when you wake up, before you get up and out of bed. Ideally measure at around the same time every day (within +/- 2 hours).

When to exclude temperatures

Certain circumstances may affect your basal temperature. This can lead to variating temperatures and make it harder for the algorithm to track your cycle. To help our algorithm learn about your cycle and accurately find ovulation, use the “Exclude temperature” function in the app if you:

Feel hungover
Slept differently (>2 hours more/less than usual)
Feel sick

Remember that everyone is different with different routines and, for instance, little sleep might affect you more or less than others. Exclude your temperature only if you feel that something was out of the ordinary for you and you feel differently this morning because of it.

Medication can also affect your temperature. If you take regular medication or anti-pyretics (fever reducing substances), it’s worth consulting with your doctor to discover its impact on your basal body temperature.

Changing your thermometer

If you need to replace your thermometer, do this at the start of your period. A basal thermometer is highly accurate, but from one thermometer to another, there can be a small difference in how each one measures. For example, if one thermometer is showing one temperature, the second can show a 0.1°C difference. As the app is looking for the smallest differences in temperatures to be able to locate where you are in your cycle, you should only use one thermometer at a time. Do not change these during the course of a cycle, instead wait until a new cycle has started before changing your thermometer.

Natural Cycles and Oura Ring

How to set up

After logging in to the Natural Cycles app for the first time, you are automatically directed to the connection flow which will help you set up the syncing between Natural Cycles and Oura. If you are transitioning from using Natural Cycles with a thermometer to using Natural Cycles with the Oura Ring, you should start with the Oura Ring at the start of your period.

How to use

Follow the user manual provided by Oura to measure temperature data trends during the night. In the morning, follow these steps to get your fertility status for the day:

Sync your Oura Ring with the Oura App. The reading will be automatically synced with your Natural Cycles app as soon as it is automatically uploaded to “Oura on the Web” cloud storage. When the reading has been registered, the Natural Cycles app will indicate the time at which it synced with Oura.

Open your Natural Cycles app and add any other data, like LH test results or period.
Check your updated fertility status for the day in the Natural Cycles app

Note: Oura Ring provides Natural Cycles with temperature trends which Natural Cycles processes into a single, absolute temperature value used by the Natural Cycles algorithm. Do not use these values to make medical decisions (ex: diagnose fever).

Note: If you have a condition that aff ects nocturnal skin temperature, using an Oura Ring as an input source to Natural Cycles is not recommended.

Note: If you need to change your Oura Ring for any reason, you should start using your new ring at the start of your period.

When to exclude temperature variation data

Certain circumstances may affect your data. This can make it harder for the algorithm to track your cycle. To help our algorithm learn about your cycle and accurately find ovulation, use the “Exclude temperature” function in the app if you:

Feel hungover
Feel sick

Exclude your temperature variation data only if you feel that something was out of the ordinary for you and you feel differently this morning because of it.

Natural Cycles and Apple Watch

How to set up

After logging in to the Natural Cycles app for the first time, you are automatically directed to the connection flow which will help you set up the syncing between Natural Cycles and Apple Health. If you are transitioning from using Natural Cycles with a different temperature source to using Natural Cycles with Apple Watch, you should start with Apple Watch at the start of your period.

How to use

Follow the user manual provided by Apple to measure temperature during the night. The temperature will be automatically transferred to Natural Cycles. In the morning, follow these steps to get your fertility status for the day:

Open your Natural Cycles app and add any other data, like LH test results or period.
Check your updated fertility status for the day in the Natural Cycles app

Note: Do not use the temperature values provided by Apple Watch to make medical decisions (ex: diagnose fever).

Note: If you have a condition that aff ects nocturnal skin temperature, using Apple Watch as an input source to Natural Cycles is not recommended.

Note: If you need to change your Apple Watch for any reason, you should start using your new device at the start of your period.

When to exclude temperature data

Feel hungover
Feel sick

Exclude your temperature data only if you feel that something was out of the ordinary for you and you feel differently this morning because of it.

Natural Cycles products

Natural Cycles offers four modes for our users to choose from depending on their fertility goal:

NC° Birth Control – for preventing pregnancy
NC° Plan Pregnancy – for increasing chances of conception
NC° Follow Pregnancy – for monitoring the course of a pregnancy

NC° Postpartum – for recovering from childbirth

These four modes can be chosen by the user prior to signing up and then within the app, if the user would like to switch between modes.

Contraception: NC° Birth Control

How it works

Your daily morning routine with Natural Cycles is as follows:

With thermometer: Measure your temperature when you wake up as described in the ‘Natural Cycles and Thermometer’ section
- With Oura Ring: Sync your data when you wake up as described in the ‘Natural Cycles and Oura Ring’ section.
- With Apple Watch: Sync your data when you wake up as described in the ‘Natural Cycles and Apple Watch’ section.
Add your temperature (if using a thermometer) and whether you have your period into the app. The view to add data will automatically open, or you can press the ‘+’ icon in the top right-hand corner. You can also add additional data, such as the result of ovulation (LH) test. Once you save today’s data, the app will calculate your status for the day.
Check your fertility status for the day – every day. The app will provide your fertility status directly after your first set of data is entered. Your status for the day is displayed in red and green colors throughout the app.

Green = Not fertile

Green days indicate you are not fertile and can have sex without protection. Green days are indicated by a green outlined circle with the words “Not fertile” inside.

Red = Use protection

Red days indicate you are likely to be fertile and at risk of becoming pregnant. Use protection (such as condoms or another form of barrier protection) or abstain in order to prevent a pregnancy. Red days are indicated by a red outlined circle with the words “Use protection” inside.

The app will indicate your ovulation as well as when you have entered and are expected to have your period. The application also shows predictions for upcoming days and months. The predictions may change and should not be used as the fi nal result, which is why you should check your status for the day – every day.

Summary of clinical studies – how eff ective is Natural Cycles for contraception?

Natural Cycles is 93% eff ective under typical use. Under perfect use, i.e. if you never have unprotected intercourse on red days, Natural Cycles is 98% eff ective.

Clinical studies have been conducted in order to evaluate the eff ectiveness of Natural Cycles for contraception. The current version of the algorithm (v.3) has been investigated on 15,570 women (on average 29 years old). At the end of the study, the following commonly used failure rates were determined:

The app has a method failure rate of 0.6, which is a measurement of how often the app incorrectly displays a green day when the woman is actually fertile and gets pregnant after having unprotected intercourse on this green day. This means that 0.6 out of 100 women who use the app for one year get pregnant due to this type of failure.

The app has a perfect use Pearl Index of 1, which means that 1 out of 100 women who use the app for one year and who get pregnant will do so either because:
- They had unprotected intercourse on a green day that was falsely attributed as non-fertile (i.e., method failure); or
- They had protected intercourse on a red day, but the chosen method of contraception failed.

The app has a typical use Pearl Index of 6.5, which means that in total 6.5 women out of 100 get pregnant during one year of use due to all possible reasons (e.g. falsely attributed green days, having unprotected intercourse on red days, and failure of the contraceptive method used on red days).

Summary of clinical data from 15,570 women on the eff ectiveness of Natural Cycles of the current algorithm version.

Algorithm Version

Study Date Range

women

Exposure time

(Women-years)

pregnancies

[worst-case]

Typical use PI (95% conﬁdence interval)

[worst-case]

Method failure rate

(95% conﬁdence interval)

v.3

Sept 2017 –

15,570

7,353

475

6.5

0.6

Apr 2018

[584]

(5.9-7.1) [7.9]

(0.4-0.8)

Effectiveness of Natural Cycles for two subgroups – women who used hormonal contraception within 60 days prior to using the app and women who did not use hormonal contraception within 12 months prior to using the app.

Subgroup	Typical Use PI (95% conﬁdence interval)
Recent Hormonal Contraception	8.6 %
3779 women	(7.2-10.0)
No Hormonal Contraception	5.0 %
8412 women	(4.3-5.7)

You can find an overview of the effectiveness of diff erent contraceptive methods in the Appendix of this manual. This will help you to understand the expected effectiveness of all forms of contraception.

Instructions if you are discontinuing hormonal contraception

Type of Contraception	When can you start Natural Cycles?
The Pill (Combined, Medium or Mini)	We recommend that you ﬁnish all the active pills of your packet. You can start using Natural Cycles as soon as you ﬁnish. You will have a high number of red days to begin with but this will improve over time.
Hormonal IUD (Intrauterine Device)	You can start using Natural Cycles the day after it has been removed.
Contraceptive Implant	You can start using Natural Cycles the day after it has been removed.
Hormonal Patch, Hormonal Contraceptive Ring	You can start using Natural Cycles the day after it has been removed. You will have a high number of red days to begin with this but this will improve over time.
Contraceptive Injection	You can start using Natural Cycles when the eﬀect of the injection has worn oﬀ. This takes 8-13 weeks depending on which injection you had.

If you are discontinuing hormonal contraception you may first experience a withdrawal bleed, which is much lighter than your true period. You will normally get your true period a few weeks later. Withdrawal bleeding should not be entered in the app as “period”.

Note: a copper IUD does not contain hormones and does therefore not inhibit ovulation. You can thus use Natural Cycles alongside a copper IUD to get insights on your body and menstrual cycle without having to use a barrier method on red days.

If you become pregnant on Natural Cycles

If your period is overdue and your temperature does not drop, you may be pregnant and the app will encourage you to take a pregnancy test to confirm the pregnancy. If the test is positive, please talk to your doctor and indicate it in the app.

NC° Plan Pregnancy

When you are planning a pregnancy, select Natural Cycles° Plan Pregnancy while signing up in the app. If you are already signed into the app, you can go to the settings page and choose NC° Plan Pregnancy. In this mode, your fertility is displayed as a scale, so you can identify the days you are most likely to become pregnant. The same morning routine as in NC° Birth Control mode applies here as well – measure, add or sync data and check your fertility status.

When you’re planning a pregnancy, we recommend taking LH tests since the occurrence of LH coincides with your most fertile days. If your period is overdue and your temperature does not drop, the app will encourage you to take a pregnancy test to confirm the pregnancy.

NC° Follow Pregnancy

Once you are pregnant, the app can be used as a pregnancy calendar and you can follow your weekly development and the development of your baby.

NC° Postpartum

After you have given birth, you have the option to enter NC° Postpartum mode. NC° Postpartum guides you through the physical and mental recovery of childbirth with resources tailored to help support your overall health and well-being during this temporary transitional phase. While taking your temperature is not required, measuring is encouraged as it helps the NC° algorithm detect when your fertility returns. Until the NC° algorithm detects your ovulation, it will give you Red Days. You can exit NC° Postpartum at any time.

Demo Mode

In Demo Mode you can see how the app could look with a few cycles of data, but you cannot add any of your own data. This is for demonstration purposes only, demo mode cannot provide you with any fertility information.
If you are currently on hormonal contraception you will access the app in Demo Mode. Once you stop using hormonal contraception you can then easily access the full version of the app. The app will now function for contraception or for planning a pregnancy.

Problems/ Troubleshooting

If you cannot access the application, the application is malfunctioning, or if you suspect something is wrong with your current fertility status, please follow the steps below:

Use protection, such as a condom or another form of barrier protection, until the error has been fixed.
Please contact our service desk via help.naturalcycles.com and our trained support agents will assist you.
Serious incidents involving this device should be reported both to Natural Cycles and to the competent authority in your country. A ‘serious incident’ means any incident that directly or indirectly led, might have led or might lead to any of the following:
- the death of a patient, user or other person,
- the temporary or permanent serious deterioration of a patient’s, user’s or other person’s state of health,
- a serious public health threat;

Application Overview

Your fertility status for the day is shown through diff erent views within the app.

Calendar tab

This tab provides the overview of today’s fertility and gives insights into the data logged in the past through various views as described below.

Today view

On this screen, you will get all of the info you need in one glance. A screen to enter your temperature pops up automatically when you open your app in the morning. Once you’ve entered your data, your fertility status will appear as a colored circle. Below the circle, you will see the weekly predictions and additional information. You can add or update your input data, such as temperature, period, or LH tests, at any time by tapping the ‘+’ icon.

Month view

Tap the “Month” tab in the calendar view to access the monthly view. Here you can see your predicted red and green days for the month, as well as when you are predicted to ovulate and have your period. These may change over time, so you should only rely on the information provided in the “Today” view for contraceptive or pregnancy planning purposes. You can easily access your past data by tapping on any past day.

Graph view

The graph is a visualization of your temperature curve which will continue to develop as you measure throughout your cycle. Information about ovulation, period, and fertile days is also visible. Swipe from left to right to view your past cycles, and zoom in and out to compare them to each other. You can also access the compare mode to compare your period and cycle length, temperature variation, ovulation window and day, and tracker graph.

Top menu

Under the top menu, you can access and manage all the information regarding your personal profi le, the app and privacy settings, and your account including subscriptions. Here you can also manage whether or not you will get reminders about when to use protection, take an LH test, expect PMS, measure your temperature and check your breasts. Note that you must enable Natural Cycles to send you push notifi cations in your device settings to receive these.

Offline mode

When you are offline you can continue to add your temperature and other data to the app. When offl ine, the app does not calculate your fertility status. Instead, the app will show an orange outlined circle indicating your status as “Use protection”. Use protection (such as condoms or another form of barrier protection) or abstain until you are back online and the app has calculated today’s fertility status.

Platform description

Natural Cycles Application Version: 5.0.0 and onwards

Medical Device version: D

Devices that may be used to access the application:

A mobile phone running Android OS (version 10 or above) or iOS (version 16 or above), 250 kbps or faster internet.
A computer or tablet with an Internet browser: Google Chrome, Apple Safari. 250 kbps or faster internet.

Accessing the Instructions for Use

The Instructions for Use can be found online on the Natural Cycles website (https://naturalcycles.app/IFU) and in your app under the “Regulatory” page. If you would like a paper copy of the Instructions for Use we will send you one at no cost. Contact customer support with your request.

Cease using Natural Cycles

When you sign up for Natural Cycles, whether it’s for a Monthly or Yearly subscription, you will need to cancel it if you don’t want your subscription to be automatically renewed for the next renewal period. Cancellation of your subscription must be done at least 24 hours before the subscription is scheduled to be renewed. Please refer to help.naturalcycles.com for a full description on how to cancel your subscription successfully. Please refer to our Privacy policy for further information on how Natural Cycles processes your data.

Security

Natural Cycles maintain a high security and data privacy level in our application. The application is monitored for security events and data breaches. If a security event or data breach should occur, the issue will be contained and resolved with urgency according to our established processes and you as a user will receive the information you need regarding your continued safe and secure use of the application.

It is strongly recommended that you choose a strong password to protect your account from unauthorized use. While not recommended, if you should choose to share your login with somebody, you do so at your own risk. Keep in mind that you can always revoke access by changing the password to your account and contacting support in order to close existing sessions.

Watch out for emails or messages asking you to provide your Natural Cycles login details. Natural cycles will not usually send you emails asking for your password, unless you have initiated this process yourself via support or a password reset.

If you detect or suspect a cybersecurity event, please contact our service desk via help.naturalcycles.com and our trained support agents will assist you.

General information

Explanation of symbols

Manufacturer

Caution

User Manual/Instructions for Use

Name of the Manufacturer:

NaturalCycles Nordic AB

Address of the Manufacturer:

St Eriksgatan 63b 112 34 Stockholm Sweden

Customer support:

help.naturalcycles.com

Device Name:

Natural Cycles

APPENDIX

This table provides information about the eff ectiveness of diff erent contraceptive methods ranging from least eff ective to most eff ective under typical use. Reference: Contraceptive Technology (Table 26 – 1). 21st Edition, 2018.

Percentage of women experiencing an unintended pregnancy during the ﬁrst year of typical use and the ﬁrst year of perfect use of contraception and the percentage continuing use at the end of the ﬁrst year. United States.
Method	% of women experiencing an unintended pregnancy within the First Year of Use	% of women continuing use at one year³
Method	Typical use¹	Perfect use²
No method⁴	85	85
Spermicides⁵	21	16	42
Female Condom⁶	21	5	41
Withdrawal	20	4	46
Diaphragm⁷	17	16	57
Sponge	17	12	36
Parous Women	27	20
Nulliparous Women	14	9
Fertility awareness-based methods⁸	15		47
Ovulation method⁸	23	3
TwoDay method⁸	14	4
Standard Days method⁸	12	5
Natural Cycles⁸	8	1
Symptothermal method⁸	2	0.4
Male condom⁶	13	2	43
Combined and progestin-only pill	7	0.3	67
Evra patch	7	0.3	67
NuvaRing	7	0.3	67
Depo-Provera	4	0.2	56
Intrauterine contraceptives
ParaGard (copper T)	0.8	0.6	78
Skyla (13.5 mg LNG)	0.4	0.3
Kyleena (19.5mg LNG)	0.2	0.2
Liletta (52mg LNG)	0.1	0.1
Mirena (52mg LNG)	0.1	0.1	80

Nexplanon	0.1	0.1	89
Tubal occlusion	0.5	0.5	100
Vasectomy	0.15	0.1	100

Emergency Contraceptives: Use of emergency contraceptive pills or placement of a copper intrauterine contraceptive after unprotected intercourse substantially reduces the risk of pregnancy.

Lactational Amenorrhea Method: LAM is a highly eff ective, temporary method of contraception.9

Among typical couples who initiate use of a method (not necessarily for the first time), the percentage who experience an accidental pregnancy during the first year if they do not stop use for any reason other than pregnancy. Estimates of the probability of pregnancy during the first year of typical use for fertility awareness-based methods, withdrawal, the male condom, the pill, and Depo-Provera are taken from the 2006–2010 National Survey of Family Growth (NSFG) corrected for under-reporting of abortion. See the text for the derivation of estimates for the other methods.
Among couples who initiate use of a method (not necessarily for the first time) and who use it perfectly (both consistently and correctly), the percentage who experience an accidental pregnancy during the fi rst year if they do not stop use for any other reason. See the text for the derivation of the estimate for each method
Among couples attempting to avoid pregnancy, the percentage who continue to use a method for 1 year.
This estimate represents the percentage who would become pregnant within 1 year among women now relying on reversible methods of contraception if they abandoned contraception altogether. See text.
150 mg gel, 100 mg gel, 100 mg suppository, 100 mg fi lm.
Without spermicides.
With spermicidal cream or jelly
About 80% of segments of FABM use in the 2006-2010 NSFG were reported as calendar rhythm. Specific FABM methods are too uncommonly used in the U.S. to permit calculation of typical use failure rates for each using NSFG data; rates provided for individual methods are derived from clinical studies. The Ovulation and TwoDay methods are based on evaluation of cervical mucus. The Standard Days method avoids intercourse on cycle days 8 through 19. Natural Cycles is a fertility app that requires user input of basal body temperature (BBT) recordings and dates of menstruation and optional LH urinary test results. The Symptothermal method is a double-check method based on evaluation of cervical mucus to determine the first fertile day and evaluation of cervical mucus and temperature to determine the last fertile day.
However, to maintain eff ective protection against pregnancy, another method of contraception must be used as soon as menstruation resumes, the frequency or duration of breastfeeds is reduced, bottle feeds are introduced, or the baby reaches 6 months of age.

Version History

VER.	DATE	DESCRIPTION
2.19	2023-07-25	Updated iOS version requirement for Apple Watch users. Updated medical device version. Updated app version. Updated date of release. Added instructions on how to use Natural Cycles together with Apple Watch.	The changes to the IFU provide users with instructions on how to use Apple Watch with Natural Cycles for temperature data. The changes to the IFU introduce a new temperature data source but there is no impact on indications for use, warnings or precautions. QMS documents are being updated to support this change.
2.20	2024-05-02	Added information about NC° Postpartum Mode.	The changes to the IFU provide users with information regarding NC° Postpartum Mode. The changes to the IFU introduce a new wellness mode within NC but there is no impact on indications for use, warnings or precautions. QMS documents are being updated to support this change.
2.21	2024-09-24	Added Apple Watch 10 as a compatible temperature source for the Natural Cycles application.	The changes to the IFU update the versions of the Apple Watch that can be used as inputs to the Natural Cycles application. The changes to the Standard IFU do not have an impact on indications for use, warnings, or precautions. QMS documents are being updated to support this change.
2.22	2024-10-24	Added Oura Ring Gen 4 as a compatible temperature source for the Natural Cycles application. Updated minimum system operating requirements to Version 10 and above for Android OS and version 16 and above for iOS.	The changes to the IFU update the versions of the Oura Ring that can be used as inputs to the Natural Cycles application and raise the minimum system operating requirements. The changes to the Standard IFU do not have an impact on indications for use, warnings, or precautions. QMS documents are being updated to support this change. Since the IFU change is so minor it was deemed not required to rerun the 1133 – IFU Review Protocol.
2.23	2025-03-07	Added URL for accessing Natural Cycles IFU.	The changes to the IFU are to align with changes to the EU version of the IFU (which is being updated to comply with EU AI position paper). The changes to the Standard IFU do not have an impact on indications for use, warnings, or precautions. QMS documents have been updated as needed to meet these requirements. Since the IFU change is so minor it was deemed not required to rerun the 1133 – IFU Review Protocol.

Document Approval

FAQ

Q: Is Natural Cycles suitable for women with irregular menstrual cycles?
- A: Natural Cycles may not be as effective for women with irregular cycles, as predicting fertility can be more challenging in such cases. It is recommended to consult a healthcare provider for the best contraceptive option.
Q: Does Natural Cycles protect against sexually transmitted infections?
- A: No, Natural Cycles does not protect against STIs. It is advised to use condoms or other barrier methods to prevent STIs.
Q: How effective is Natural Cycles in preventing pregnancy?
- A: Natural Cycles is 93% effective under typical use and 98% effective with perfect use. It is essential to follow the app’s guidelines diligently for optimal effectiveness.

Documents / Resources

NORDIC Natural Cycles Stand Alone Software Application [pdf] User Manual
Natural Cycles Stand Alone Software Application, Cycles Stand Alone Software Application, Stand Alone Software Application, Software Application

References

User Manual

NORDIC Natural Cycles Stand Alone Software Application

Product Usage Instructions