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Despite millions of women using birth control, getting pregnant, and giving birth, it’s remarkable how little women are taught about reproductive health and their own bodies. And considering the important role a woman’s menstrual cycle plays in her overall health and fertility, women deserve proper education to make informed health decisions. Natural Cycles, the company that developed the first FDA-cleared birth control app, is on a mission to empower women by giving them the education – and therefore power – to do just that.

The Natural Cycles app is powered by an algorithm that uses body temperature and other fertility indicators to confirm a woman’s daily fertility status – aka it tells each user if they can become pregnant each day or not. It was developed by Dr. Elina Berglund Scherwitzl, a scientist who was looking for an effective, non-hormonal, and non-invasive form of birth control that could also help her plan pregnancy when she was ready to start a family. Years later, the NC° app has millions of registered users around the world who have trusted it to guide them on their own fertility journey.

While the science behind Natural Cycles is complex, its process isn’t. Users take their temperature with a thermometer or sync their temperature data with a wearable such as the Oura Ring. From there, Natural Cycles’ algorithm takes over, using body temperature with other fertility indicators to confirm a user’s individual fertility status. On a fertile day (a “red day” in the app) the user needs to abstain from unprotected sex if they are trying to avoid pregnancy. On a non-fertile day (a “green day” in the app) the user is not at risk of becoming pregnant that day.

The algorithm is what sets Natural Cycles apart from other fertility apps on the market – it’s actually a regulated medical device that is intended to be used to prevent pregnancy. No other app currently on the market is intended to do that. And because it is a regulated medical device, Natural Cycles upholds strict privacy protection measures to protect user’s sensitive data. In fact, it was recently named one of two fertility apps that received a favorable privacy rating from Mozilla.

It’s easy to see why women love Natural Cycles when reading online reviews – the app has more than 50,000 reviews in the Apple App and Google Play stores for a 4.7-star rating out of 5 stars. 

“I love everything about the app and the process. Using Natural Cycles has taught me to listen to my body but also to take care of it with more regular sleep and care,” wrote Savanna, Natural Cycles user for two years.

Use the code NC20 to get 20% off an annual Natural Cycles subscription, plus a free thermometer.

Prices subject to change. Disclaimer: While Natural Cycles is intended only for women 18 and older, the app offers no protection against the spread of sexually transmitted infections (STIs), so users are still advised to take precautions whenever they engage in sexual activity.