Apple’s study on women’s health releases preliminary data with insights on menstrual health symptoms

Apple Women’s Health Study is being conducted with the aim to help destigmatise menstruation and menstrual symptoms.

Apple used its Research app to get women in the US to contribute to the research using their iPhones and their Apple Watches. (Apple )

The Apple Women's Health Study team at Harvard T.H. Chan School of Public Health has released a preliminary study update that offers insights on menstrual symptoms. The study is being conducted with 10,000 participants across the US involving volunteers across age groups and races.

The study, which aims to understand menstrual cycles and how they relate to various health conditions like polycystic ovary syndrome, infertility, and menopausal transition, was kicked off in 2019 and is still ongoing and is being conducted in partnership with the Harvard T.H. Chan School of Public Health and the NIH's National Institute of Environmental Health Sciences (NIEHS).

For now, the preliminary data that's been shared sheds some light on menstrual symptoms and contributes in the larger research on menstruation and women's health that should help destigmatise menstruation and promote better research.

While many physicians consider women's menstrual cycles to be vital windows into their overall health, this topic itself is grossly under-researched and medical research on this has been limited to small studies that are by no means representative of a broader population.

The biggest hurdle for these studies has been the lack of substantial scientific data on women's menstrual cycles and symptoms and this has historically lead to a dismissal of a case where it is necessary to study this on a larger scale. And it has also been considered overreaction and oversensitivity.

There are period tracking apps available both on the Play Store and on the App Store where women can log in their cycles and symptoms - like Clue and Flo. However, it is not possible to get such scattered data together.

Apple used its Research app to get women in the US to contribute to the research using their iPhones and their Apple Watches. The data collected includes cycle tracking and other health data and participants have full control over the data they share with the study and full transparency into how this data is being used for the study.

Harvard Chan School researchers' preliminary analysis of data, from a cohort of the first 10,000 participants who enrolled in the study and responded to a demographics survey, revealed a wide range of menstrual cycle symptoms experienced by them, including ones that are less common. 

The range of menstrual symptoms recorded across participants in the survey.  (Apple )

The range of menstrual symptoms recorded across participants in the survey.  (Apple )

The most common symptoms included abdominal cramps, bloating, tiredness - all of which were experienced by at least 60% of the women participating in the study. More than 50% of the participants also experienced acne and headaches. Then there were less common symptoms like diarrhoea and sleep changes that were logged in by about 37% of the participants.

Initial analysis also suggests these symptom trends hold true across a wide range of demographics, including age, race, and geographic location. For example, across Black, Hispanic, and white participants, the most commonly reported symptoms were abdominal cramps, bloating, and tiredness.

Menstrual symptoms experienced by participants across race and ethnicity.  (Apple )

Menstrual symptoms experienced by participants across race and ethnicity.  (Apple )

"The menstrual cycle is a very important part of our health, and it's also a window into the healthy functioning of the whole body. Irregular or abnormal periods can also be an insight into whole-body health or disease, so when patients come and talk to me in the clinic about their menstrual cycles and periods, one of the first questions I ask is -When was your last menstrual period?” said Dr. Shruthi Mahalingaiah, who is one of the principal investigators for the study and an assistant professor of environmental, reproductive, and women's health in the department of Environmental Health at the Harvard T.H. Chan School of Public Health

"What researchers and physicians in the scientific community want and need to know is more about the menstrual cycle, its relation to long-term health, as well as more about what environmental factors might affect cycle length and characteristics. With this study, we are creating a larger foundational data set on this topic, which can eventually lead to further discovery and innovation in women's health research and care,” Mahalingaiah explained.

If you live in the US and want to be a part of this study and own an iPhone and an Apple Watch, you can download the Research app to enrol. You must be at least 18 years old (at least 19 in Alabama and Nebraska and at least 21 in Puerto Rico) and must have menstruated at least once in your life to be a participant.

How to track your cycle on the iPhone and Apple Watch

For the rest of us, is you want to track your cycle on the iPhone and Apple Watch, you need to -

- Go to the Health app on the iPhone or Cycle Tracking on the Apple Watch.

- Here you can log a period day, or spotting and also your symptoms. You can also add Factors that can influence your cycle like pregnancy, lactation and contraceptive use.

- With this information the Cycle Tracking feature can let you know when your next period or fertile window is about to start with notifications and this will also help you track if your periods are regular or not.