Could an app help scientists better understand menstruation, fertility, and menopause? On the latest episode of This Week in Health, Shruthi Mahalingaiah and JP Onnela talk about the groundbreaking Apple Women’s Health Study.

Shruthi Mahalingaiah, an assistant professor of environmental, reproductive, and women’s health, and JP Onnela, an associate professor of biostatistics, are two of the Harvard Chan School researchers involved in a new study seeking to gain more insight into women’s health. Using an app on their Apple devices, women can share information about their monthly cycles, as well as certain behavioral factors such as physical activity and mobility, to help researchers advance understanding of menstrual and gynecological health. To learn more about the study, or to participate, visit


Full Transcript

[MUSIC PLAYING] DAVID LEVIN: You’re listening to Harvard Chan– This Week in Health. I’m David Levin.

SHRUTHI MAHALINGAIAH: One of the things that’s exciting to me is the potential to reduce maternal mortality in areas of the world which are greatly suffering. SHRUTHI MAHALINGAIAH

DAVID LEVIN: That’s Shruthi Mahalingaiah, a physician scientist at the Harvard Chan School. She’s one of the researchers behind the new Apple Women’s Health Study, which uses an iPhone app to collect long-term health data from thousands of women worldwide. Its goal– to understand women’s menstrual cycles and their relationship to conditions like infertility and menopause.

It might even be used to flag reproductive health issues early so women can seek treatment before major problems emerge. It’s the first ever women’s health research study of this scale. And it’s being done in partnership with both Apple and the National Institute of Environmental Health Sciences.

In this episode, we talk with Dr. Mahalingaiah and Dr. JP Onnela. He’s a biostatistician at Harvard Chan School who codesigned the study. And he’s overseeing the huge amount of data it’ll create. So Shruthi, a question for you. I’m hoping maybe you can give me some context for this study. Why is a large-scale study of menstruation needed now? And what gap does that fill in the medical and scientific knowledge that we have?

SHRUTHI MAHALINGAIAH: The one main question anchoring all of this is when a woman comes into the clinic, we often ask, when was your last period? Or can you explain how have your periods been? The early 2000s before tracking apps and before Apple created the iPhone, people would come back to me.

They couldn’t articulate their cycle history. And they’d fill out a cycle calendar for three to six months so I could get a sense of regularity. We thought, getting a baseline is good, but having a sense of menstrual cycles over the past and collecting them prospectively would be even better. So we started partnering with tracking apps.

And I do think that there is a great need to understand menstrual cycle variation across not only in the numerical contexts of the number of days between cycles, but also how women experience their cycles so that we could better serve them and both emotionally, physically understand how to diagnose conditions earlier. Oftentimes, several gynecologic diseases take years to come to a diagnosis. It might take up to seven years to come to a diagnosis of endometriosis, for example.

DAVID LEVIN: So what data are you actually collecting, JP?

JP ONNELA: So in this particular study, surveys are the form of active data that we’re using. We’ve implemented really truly has been leading this effort sort of standardized surveys and questionnaires about women’s health.

The other data component, we use the term passive data. And for us, the term passive really means that it’s collected regardless of your participation to study. So it’s an unobtrusive way of collecting data. The data collection is kind of happening there in the background. We can collect data about your location, about your social activity, about your physical activity using accelerometer and gyroscope data.

And I think that the one thing that comes to everyone’s mind immediately is, well, isn’t this kind of intrusive data collection? And I think that, yes, absolutely, it is. But everybody in our studies gives their full consent to have these data collected. So in all of these types of studies, there has to be a study app that’s installed on the phone. A person has to be invited to participate in the study. And provided they meet all the inclusion criteria, then they may enroll in the study.

DAVID LEVIN: So how does this look from a user perspective? Someone downloads this research app, and then what? They’ll see a survey they have to do every once in a while, and the rest of the data is collected in the background from the rest of the phone?

JP ONNELA: Essentially, yes. So we have monthlyish surveys, larger surveys and–

SHRUTHI MAHALINGAIAH: There are surveys on different temporal schedules for how long they are, but a baseline at entry and then monthly surveys if you are currently menstruating, also if you’re breastfeeding. So depending on your state of being will determine the chronicity of some of the survey.

DAVID LEVIN: So what exactly can capturing this kind of information tell you about women’s health?

SHRUTHI MAHALINGAIAH: One of the unique aspects of this study is the phone or the watch is collecting information to be able to risk stratify someone into at risk or healthy for a particular issue. I think that this has a huge potential to transform how we roll out preventive measures to keep our populations as healthy as possible. Could we see behavior patterns shift and change across the menstrual cycle?

Could we detect something that might alert us to women who are at risk for PMS or premenstrual dysphoric disorder and alleviate their symptoms so that they’re not suffering at home? A lot of these issues, it’s very hard for women to have awareness and be taken seriously in certain contexts and get the help they need.

If someone is experiencing severe pain during their period or between periods due to something called endometriosis, presumably their social network might be collapsed compared to others, or their geographic location might be altered compared to healthy normal women with robust experiences of no pain.

In addition, one of the amazing things with this technology and sometimes with app-based technology is we can understand better a person’s environmental exposures based on their geolocation so proximity to major roadways or factories or industrial wastelands or superfund sites. And this is a key area of research as we grow to understand how environmental toxins can actually reduce fertility and increase risk for infertility.

DAVID LEVIN: So it sounds like that’s going to be incredibly useful for public health research in the future. But what about if you have someone with the app, and you have a certain health condition that comes up or something that’s flagged in those data points, what could change for that person as a result of this app?

SHRUTHI MAHALINGAIAH: So that’s a really interesting question, something I’ve been thinking about, to be able to look back at six months of menstrual cycle data and apply an interactive survey. Let’s say a person’s entering their menstrual cycle data. And the last six months are reviewed. And there’s increased cycle variation or irregularity noted.

They might get a survey that’s interactive and asks them about their symptoms. Are they having galactorrhea or a milky discharge from their breasts? Are they having insomnia? Have they had a change in their exercise? Have they had a recent change in weight? Are they experiencing more acne or hair on their face or body than usual? There’s so many other questions that can be incorporated to understand where that pathology could be coming from.

So one can imagine entering this information and getting a risk score for potential ovulation disorder or endocrine disorder, uterine pathology, such as a polyp or fibroid potentially, and getting a printable report they could take to their physician or that might download immediately into an electronic health record so their physician can see it and come to the next steps for disease detection.

DAVID LEVIN: So not necessarily a diagnosis, but at least a flag saying you should probably see a doctor.


DAVID LEVIN: And for women listening, why should they participate? What would you say to them?

SHRUTHI MAHALINGAIAH: There are a couple of reasons. One is altruistic, to contribute their voice to understanding their experience as it pertains to being a woman, menstrual cycle, pregnancy, childbirth, and longitudinal health, including the menopausal transition, that we really don’t have enough understanding of as it impacts our lives through being mothers, or working, or not being mothers, and being child free, to have everyone’s voice represented would be very important.

On the discovery side, I think that each group of the collaboration from Apple to the National Institute of Environmental Health Science, we each have different things that we want to discover and contribute from this data. And I can speak from us here at Harvard Chan, the potential to be able to design preventive materials, methods, interface to keep women healthy for as long as possible across our lives would be my take-home point from this.


JP ONNELA: This is perhaps an obvious point to some listeners, but I think it’s important to stress that the reason we know how to treat any medical condition today is because people have done research into that condition in the past. Other individuals have participated in studies so that we can now treat several conditions so much better than 50 years or a hundred years ago.

From my point of view, this is an opportunity for individuals to participate what could really become the largest study on women’s health in a way that it doesn’t matter if you’re located in rural, if you’re in a small village or small town.

You don’t have to be located at one of these major medical hubs, maybe like Boston or New York City or LA. You can participate anywhere. All you need is the phone. And I think that’s exciting to be part of this discovery. We couldn’t do research without subjects.

And I think that from my point of view, the accessibility of the study and the fact that anywhere in the US, you can participate. You can contribute valuable data to a study that could really change the way many of these conditions are treated in the future. That seems incredibly important to me.

DAVID LEVIN: So what does it mean for Harvard Chan to join forces with an industry partner like Apple? It’s kind of a tech behemoth. What research does that enable that you wouldn’t be able to do otherwise?

JP ONNELA: So Apple is, of course, they are the developers of the iPhone. And they have a sizable market share in the US and also globally. And one thing about this type of research, which is I think not always understood, is that it’s not just a question of developing the initial version of the research app.

It’s a question of maintaining that, having a back end that goes with the data collection that supports the front end. And I don’t think there is a better partner than Apple to work with in terms of making sure that the user has a seamless experience which matters for study adherence and also making sure that we didn’t have any glitches in the app. Working with Apple has been great in this regard.

They have a very, very high standard for privacy. And privacy has been a concern throughout the design process. And also the back end, they have substantial expertise in making sure that there is a very smooth integration between the front end app and the back end piece. So working with Apple has been a very good experience for us. And also, Apple is a brand that I think most people trust. And so they’ve been a very good partner for us.

SHRUTHI MAHALINGAIAH: I think what it means is that we can hear voices from women of many geographic backgrounds and experiential backgrounds that would never have been able to be included in studies before. So to me, it’s an access. It’s increasing access to diversity in women’s health research. I think it’s critically important. And this is what makes me super excited about participating in this study as a collaborator and a participant.

And historically, being included in a study means that a person has a lot of factors that are working in their favor to participate. So either they have resources to be able to go to the clinic and spend time. They’re not required to be in their wage-related job to– they can bring their child in so that both the mother and the child can participate in the study. It’s a small fraction of the population that has this kind of time and resiliency.

And so I think that we’re going to be able to hear from and understand the experiences of a much larger population. And that’s what I think the implication of this kind of partnership is with Apple bringing in the research expertise of everyone on our team from the research side and the product development side at Apple is very exciting.

Getting the word out to women or anyone who’s menstruated once in their life is really the key. And that’s what we’re going to be working on. And it’s a very exciting area to get the word out.


DAVID LEVIN: Excellent. Well, I thank you both for joining me. It’s been a real pleasure speaking with you.

JP ONNELA: Thank you so much.

SHRUTHI MAHALINGAIAH: Thank you so much.

DAVID LEVIN: To participate in the Apple Women’s Health Study, visit That’s all one word. And click on Download the research app. You can also use the app store on your iPhone. Just search for the words Apple research.

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