Ahead of International Women’s Day, new preliminary findings from the Apple Women’s Health Study underscore the importance of paying attention to the menstrual cycle and its connection to overall health.
Many physicians consider periods a vital sign, yet this area of health is notably under-researched. The Apple Women’s Health Study is a first-of-its-kind research study conducted with the Harvard T.H. Chan School of Public Health and the National Institute of Environmental Health Sciences (NIEHS) that 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. The study is significant in its scope and scale because it invites anyone who has ever menstruated across the US to contribute to this research simply by using their iPhone.
New Preliminary Findings
Harvard Chan School researchers used survey data from the Apple Women’s Health Study to advance the scientific understanding around the relationship between persistently abnormal periods, PCOS, and endometrial hyperplasia and cancer. Looking at a preliminary analysis cohort of over 50,000 study participants, the study team found:
- 12 percent of participants reported a PCOS diagnosis. Participants with PCOS had more than four times the risk of endometrial hyperplasia (precancer of the uterus) and more than 2.5 times the risk of uterine cancer.
- 5.7 percent of participants reported their cycles taking five or more years to reach cycle regularity after their first period. 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 who reported their cycles took less than one year to reach regularity.
These updates are a first step for helping people understand risk factors for these diseases, and encouraging people to have conversations with their healthcare providers about cycle irregularity earlier.
“More awareness on menstrual cycle physiology and the impact of irregular periods and PCOS on uterine health is needed,” said Dr. Shruthi Mahalingaiah, MS, Harvard Chan School’s assistant professor of Environmental Reproductive and Women’s Health and co-principal investigator of the Apple Women’s Health Study. “This analysis highlights the importance of talking to a healthcare provider when menstruators are experiencing persistent changes to their period that span many months. Over time, we hope our research can lead to new strategies to reduce disease risk and improve health across the lifespan.”
The study team will conduct further analyses on this preliminary data for scientific publication.