Natural Cycles’ $130 Wristband Can’t Fix Its Efficacy Problem—Or Can It?

Natural Cycles is swapping thermometers for a $130 wristband—but is its FDA-cleared birth control app actually any safer? The company’s new $129.99 wearable replaces manual thermometers for its contraceptive algorithm, which received FDA clearance in 2018 after 37 of 668 Swedish women seeking abortions reported unintended pregnancies while using it.

Users can continue using the thermometer if they currently have one. The wristband syncs with the app via Bluetooth 5.0 to track skin temperature, heart rate, and sleep movement, but does not replace the app’s algorithm for contraceptive use.

It offers a 14-night battery life and is available for $129.99, included in the annual plan for $149.99, or $99.99 for existing subscribers.

Privacy concerns persist post-Roe v. Wade, though the app claims data is pseudonymized and encrypted. The wristband’s technical features contrast with ongoing criticism about the app’s real-world efficacy and its controversial track record of unintended pregnancies.