Feel safe knowing your data is protected

Yes — whether you're trying to prevent pregnancy or plan for one, the Natural Cycles app is effective from day one!
Clinical research shows NC° Birth Control is 93% effective with typical use and 98% effective with perfect use (meaning you either use protection or abstain on Red Days).

Forgetting to measure won't reduce effectiveness, but the app might give you more Red (fertile) Days if it doesn't have enough data due to a rough night's sleep or skipped measurements.

Thinking about starting a family? NC° Plan Pregnancy takes the guesswork out by confirming ovulation and predicting your peak fertility so you can get pregnant faster when you're ready. Learn more about the science behind our effectiveness.

You can measure in a way that fits your lifestyle. Natural Cycles works with a range of wearable technology, allowing you to smoothly sync your temperature data with the NC° app.

Whichever wearable you choose, the effectiveness of NC° Birth Control stays the same. Visit our devices page to explore all of our compatible integrations and learn more about your measuring options.

If you already own a compatible wearable, you can start measuring right away. New to wearables? When you sign up, you can unlock exclusive discounts on select devices.

Natural Cycles is the first and only app of its kind cleared by the FDA as birth control. Most other fertility apps assume your cycle is 28 days long. This means the fertile window they predict is not personalized to your cycle. So how can it be true to you? Our algorithm significantly reduces the risk of you receiving an incorrect fertility status since it uses your unique temperature data, which reduces the risk of unwanted pregnancy and can even help you plan for pregnancy with greater precision. 

Plus, not all period trackers keep secrets — some might even share them. With the Natural Cycles app, your data stays yours. We provide an advanced data privacy protection program called NC° Secure that is designed to keep your data safe.

Natural Cycles is just as effective if you have irregular menstrual cycles (i.e. cycles lasting fewer than 21 days or greater than 35 days in length). The Natural Cycles app adapts to your unique cycle by considering irregularities, temperature shifts, recent use of hormonal birth control, ovulation patterns, and more to provide a personalized experience.

The app’s Cycle Insights tool helps you better understand your cycle and offers tailored recommendations. It can even flag atypical patterns or irregular cycles, giving you valuable insights to discuss with your healthcare provider. Check out our NC° Cyclerpedia articles on cycle irregularity to learn more.