How effective is NC° Birth Control?

NC° Birth Control is more than an app. It’s a certified medical device that’s regulated by official bodies. And while apps can get a bad rep when it comes to data privacy, one of the reasons we charge a subscription fee is to protect our users. We take your data privacy very seriously and will never monetize your data by selling it to third parties.

No, the method is just as effective! Changes in your sleep pattern, or forgetting to measure doesn’t affect how effective NC° Birth Control is at preventing pregnancy. However, if the app doesn’t have enough data due to poor sleep or forgetting to measure, you might get more red days (when you’ll need to abstain from sex or use protection).

It’s actually different in a couple of ways! Compared to manual charting, the Natural Cycles algorithm avoids some of the human error that can happen, since it does the work for you. It also takes historical temperature and cycle data into account. Compared to calendar-based methods (such as the rhythm method) Natural Cycles provides greater accuracy in finding your personal fertile window because it's individualized to your ovulation. This puts NC° Birth Control in a higher effectiveness category than the rhythm method and other methods that assume a set cycle pattern.

As a regulated medical device, Natural Cycles is subject to rigorous testing and yearly audits. Our FDA clearance is based on the analysis of more than 15,000 women over 180,000 cycles. We are constantly monitoring the app’s performance to ensure our Pearl Index remains constant and our effectiveness rate remains the same. You can read more about our research, including our effectiveness studies, here.

Yes. The effectiveness of NC° Birth Control does not change for those with different cycle lengths or patterns. However, irregular cycles and ovulation means that the algorithm needs to give more red (fertile) days before ovulation in the event that it would happen earlier than expected. If you have very irregular cycles or PCOS, you should therefore expect to have less green (non-fertile) days and more days where you need to use protection.

The effectiveness of Natural Cycles birth control remains the same regardless of the measuring device you use (93% effective with typical use and 98% effective with perfect use). This was shown in clinical evaluations we conducted that were reviewed by the FDA. Both the Oura Ring and Apple watch have been cleared by the FDA to be used with Natural Cycles.