Apple menstrual health study shows importance of femtech features

Series 8 temperature sensor is no gimmick
Apple Cycle tracking Series 8
Wareable is reader-powered. If you click through using links on the site, we may earn an affiliate commission. Learn more

New biometric cycle tracking features landing on wearables such as the Apple Watch Series 8 and Samsung Galaxy Watch 5 can have an important role to play in women's health – a new study has shown.

A Harvard study using Apple cycle tracking data has found large numbers of women suffering from conditions that could lead to serious health outcomes.

The study by Harvard Chan School used data from the opt-in Apple Women’s Health Study, and found that 12% of participants reported a polycystic ovary syndrome (PCOS) diagnosis, which carries a 4x risk of four times the risk of endometrial hyperplasia (pre-cancer of the uterus), and 2.5x risk of uterine cancer.

The study aims to advance the understanding of menstrual cycles and how they relate to various health conditions such as polycystic ovary syndrome (PCOS), infertility, and menopausal transition.

Using iPhones, participants contribute to the study by sharing their cycle tracking data, along with other health data from their iPhone or Apple Watch.

The Apple Watch Series 8 uses body temperature data to retrospectively track ovulation and specifically looks for PCOS and shifts in cycles.

The study also found that  5.7% of participants reported taking five or more years to reach cycle regularity after their first period, and participants in that group had more than twice the risk of endometrial hyperplasia and more than 3.5 times the risk of uterine cancer compared to those whose cycles took less than one year to reach regularity.

Sumbul Desai, MD, Vice President of Health at Apple, believes that these insights have helped the company build features like cycle deviation notifications and improve period and fertile window predictions within Cycle Tracking:

"We envision a world where everyone with a period sees it for what it is: an amazing insight into their health that should be celebrated, not stigmatized," she said.

"We continue to build on this work with new features including retrospective ovulation estimates on Apple Watch Series 8 and Apple Watch Ultra, which make helpful information about the menstrual cycle more accessible to people—directly on the devices they already use every day."

By encouraging people to have conversations with their healthcare providers about cycle irregularity earlier, the study hopes to improve women's health outcomes and reduce the risks associated with menstrual irregularities.

And according to a new study published in the American Journal of Obstetrics and Gynecology, cycle deviations, like irregular or prolonged periods, affect 16.4% of women. 

That study also found that black participants had a 33 percent higher prevalence of infrequent periods compared to white, non-Hispanic participants, while Asian participants had a higher prevalence of irregular periods.

How we test

James Stables


James is the co-founder of Wareable, and he has been a technology journalist for 15 years.

He started his career at Future Publishing, James became the features editor of T3 Magazine and and was a regular contributor to TechRadar – before leaving Future Publishing to found Wareable in 2014.

James has been at the helm of Wareable since 2014 and has become one of the leading experts in wearable technologies globally. He has reviewed, tested, and covered pretty much every wearable on the market, and is passionate about the evolving industry, and wearables helping people achieve healthier and happier lives.

Related stories