Oura, maker of a health tracking ring, announced a partnership with birth control app Natural Cycles to use its wearable to monitor body temperature changes.

Users will be able to sync temperature data recorded from the Oura Ring into the Natural Cycles app instead of taking their temperature manually each morning. Natural Cycles, which received FDA De Novo clearance in 2018, uses temperature data and menstrual cycle information to determine a user's fertile window and prevent pregnancy.

The Swedish company also received the regulatory green light last year to use third-party thermometers as a part of its system to determine fertility. The filing specifically mentioned the Oura Ring. 

"We have been actively working on delivering a seamless measuring experience for our users and we were thrilled when we received FDA clearance to use the Oura Ring with our algorithm," Natural Cycles cofounder and CEO Elina Berglund Scherwitzl said in a statement. "We are proud to officially launch this partnership and work alongside a company that is similarly committed to delivering advanced health tools to women at a time when it has never been more important. With the help of Oura data, Natural Cycles is powering the future of birth control."

THE LARGER TREND

Berglund Scherwitzl, a former particle physicist, founded Natural Cycles with her husband in 2013. The app received a European CE mark in 2017. 

However, the company hit a few snags shortly after its European certification. In 2018, the U.K.’s Advertising Standards Authority found a Facebook ad that described Natural Cycles as a "highly accurate contraceptive app" and a "clinically tested alternative to birth control methods" was misleading after the agency received complaints. Natural Cycles said it removed the ad after it ran for about four weeks, and it respected the ASA's decision.

It also faced an investigation by the Swedish Medical Products Agency after a Stockholm hospital found 37 out of 668 patients seeking an abortion during September and December 2017 had been using the app for birth control. The agency later determined the rate of unplanned pregnancies is in line with the product's reported effectiveness. 

Meanwhile, Oura launched the latest version of its wearable, the Oura Ring Generation 3, in October. Though the company didn't release details, it raised an "oversubscribed" funding round earlier this year that bumped its valuation to $2.55 billion. Oura had previously scored $100 million in Series C financing in May 2021.

Clue also offers a birth control app, which received FDA 510(k) clearance last year. Unlike Natural Cycles' app, it only uses period start dates to determine fertility.