How does Natural Cycles work?

Did you know, you can’t get pregnant every day of your cycle?

Natural Cycles has 3 easy steps

When you wake up in the morning, use the Natural Cycles thermometer to take your temperature.

Diagram of the Natural Cycles app's structure: a thermometer in a mouth measuring temperature, and the app showing "Algorithm working" on the screen as the fertility prediction is calculated.


Measure in the morning

Did you know your temperature rises slightly after ovulation? Charting body temperature is not a new birth control method. However, Natural Cycles pairs this traditional method with an algorithm that learns the pattern of your unique cycle and can predict your fertile window. Use a basal thermometer to take your temperature as soon as you wake up in the morning.

Two women lying on adjacent beds measuring their basal body temperatures using Natural Cycles thermometers.
Screenshot of the temperature graph screen in the Natural Cycles app showing a user's menstrual cycle. It includes the period, ovulation, and shows fertility status on each day.

Add data

Add your unique data to the app

Input your daily temperature readings into the app - don’t worry, it’s OK if you skip some days! You’ll also need to add your period data - this lets us know when a new cycle starts, and helps us find your ovulation. You can also add extra info like cycle symptoms, changes to your mood and sex data, so you can learn even more about the pattern of your unique cycle.

Two phones side-by-side with the today screen of the Natural Cycles app visible on each. The phone on the left shows a red circle and the text "Use protection", indicating a fertile day. The phone on the right shows a green circle and the text "Not fertile".

Learn about your body

Learn your status

Once you’ve added your temperature, the app will give you a fertility status for the day. Depending on where you are in your cycle you’ll either get given a green day (not fertile) or a red day (fertile). The app will also give you handy reminders like PMS alerts and when to carry out a breast exam, so you can learn more about your body along the way.

Discover Natural Cycles today