Natural Cycles receives FDA clearance for AI-powered fertility algorithm

Natural Cycles has received its sixth FDA clearance, this time for an updated version of the algorithm underlying its FDA-cleared birth control app. The company described the update as combining statistical modeling with machine learning trained on real-world fertility data to generate more individualized fertility predictions for users, according to a news release published July 27, 2026.

The FDA clearance of the company’s next-generation NC° Fertility Algorithm was supported by evidence showing the updated algorithm maintains the app's existing safety and effectiveness profile while increasing the number of Green Days—the days on which the app indicates pregnancy protection is not needed, for many users—according to the company.

Natural Cycles stated its effectiveness rates are 98% with perfect use and 93% with typical use, placing it in the same effectiveness range as combined oral contraceptive pills, with figures supported by peer-reviewed clinical research and real-world evidence.

"The next chapter for digital contraception is making it more personalized and easier to use while maintaining the same high standard of safety,” said Kerry Krauss, MD, MPH, FACOG, senior medical advisor at Natural Cycles, in a statement.

“This FDA clearance demonstrates how advances in AI and machine learning can improve the user experience while preserving the scientific rigor expected of a regulated medical device," said Krauss.

An updated AI algorithm for birth control app

• Updated algorithm is intended to increase Green Days while maintaining existing effectiveness
• Update improves performance for users with irregular cycles
• Update is designed to better process lower-quality temperature and biomarker data
• Algorithm personalizes quicker as a user's cycle changes over time, according to the company
• Natural Cycles has filed a patent application covering elements of the updated algorithm
• Effectiveness rates cited by the company: 98% with perfect use, 93% with typical use

The company's FDA clearance history spans several years, beginning in 2018:

• 2018: FDA De Novo clearance for a birth control app.
• 2021: FDA 510(k) clearance for Oura Ring integration.
• 2023: FDA 510(k) clearance for Apple Watch integration.
• 2024: FDA 510(k) clearance including a Predetermined Change Control Plan (PCCP), creating a regulatory pathway for future hardware integrations.
• 2025: FDA 510(k) clearance allowing Natural Cycles to be offered both over-the-counter and by prescription.
• 2026: FDA 510(k) clearance for the next-generation NC° Fertility Algorithm.

PCCP pathway has enabled additional hardware integrations

The 2024 PCCP clearance has since supported the launch of the NC° Band, a wearable built for the app, along with a hardware integration with Garmin that launched in March. Natural Cycles has also received regulatory authorization in more than 8 markets outside the United States, including Europe, Canada, Brazil, Australia, South Korea, and Singapore.

Reference:

Natural Cycles Receives Sixth FDA Clearance for Next-Generation Fertility Algorithm. Natural Cycles. News release. Published July 27, 2026. Accessed July 27, 2026. https://prnmedia.prnewswire.com/news-releases/natural-cycles-receives-sixth-fda-clearance-for-next-generation-fertility-algorithm-302834425.html