A Cybersecurity Expert’s Guide to Period and Pregnancy Trackers

Millions of women today trust smartphone applications with data about their reproductive and sexual health. These apps enable users to track their menstrual cycles and all the accompanying symptoms, from energy to digestion and nausea to sex drive.

Reviews on Apple’s app store are glowing. Users have rated Clue, Flo, and Glow, three of the most popular apps, at 4.8, 4.8, and 4.7 out of 5, respectively. One woman credited her period tracker with helping her “take control of my health care needs in a way I’ve never experienced.” Another wrote, “Honestly this app saved me” by helping better manage severe premenstrual syndrome symptoms, including violent and suicidal thoughts.

But, as reporting from The Washington Post and Vox suggests, users may not fully understand the risks of giving such valuable personal data to companies that have a bottom line to consider.

Apps that track periods and pregnancy can be powerful tools to better understand your body. But you should also know how they collect and use your personal health data.

With insights from Shiu-Kai Chin, Ph.D., professor in the Syracuse University College of Engineering & Computer Science, the following guide from Engineering@Syracuse can help you make the most of the technology available to you while minimizing your risk.

Table of Contents

How Do Apps Collect Data?

Apps can help you organize your finances, try on a new hairstyle, plan a wedding, redecorate your living room, find a rideshare, split the cost of dinner, and find the closest gas station.

Compared to websites, apps tend to offer a more streamlined experience that can be tailored to your needs. Different from websites, apps collect data in and through your phone.

Smartphones have sensors that gather information about you, explained Chin. They can track the orientation of your phone and your keystrokes, the sound of your voice and your daily steps. Your phone stores all these facts about you, as well as the data you input into apps, such as the date of your last period or the results of your most recent electrocardiogram.

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What Happens to My Data?

When you open an app that stores this kind of personal data for the first time, you may be prompted to review and accept a “Terms and Conditions” document. The app might request permission to access certain features of your phone—the camera or your contacts, for example.

Unless you reject these terms, your apps can access and store this information. Chin said more people, especially those using period-tracking apps, should be aware of this reality. Once permission is given, users in the United States may not have control over their data.

This isn’t necessarily a cause for alarm. “We live in a surveillant society,” Chin said, where collecting data on citizens is common practice. Allowing authorities to access information about us helps our communities function well and businesses thrive. License plate scanners, for example, help keep the streets safe. Grocery reward cards allow stores to stock more of what consumers want and reduce waste.

Still, for data collected digitally, Chin said, “It’s unclear who owns your information.” Even more uncertain is whether this information is protected.

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What Are the Risks of Sharing Health Data Online?

Health information is especially sensitive, depending on who reads it and whether they can connect a particular data point to a specific user. And apps don’t have the same explicit protection guarantees and privacy standards accorded to medical professionals and their technology. The data collected in apps is not protected by the Health Insurance Portability and Accountability Act (HIPAA) the way data in a patient portal is.

Skeptics worry that insurers could gain access to a woman’s data and deny coverage if she cites a preexisting condition in the app. In April, a Washington Post story suggested employers could potentially monitor workers’ pregnancies in the app Ovia and adjust health benefits accordingly.

Apps that share women’s intimate data with advertisers could also cause unintended emotional harm. Writing in The New York Times, one woman lamented disclosing her pregnancy in an app, as she continued to receive ads for baby products even after logging her miscarriage. 

There’s no way to really tell who is reading our data, said Chin, even if you carefully study an app’s legal disclosure documents. So, we should assume that anybody can have it, including insurers.

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Should I Use a Health Tracker?

Health tracking apps can be useful. But, given the sensitivity of personal health data, users should carefully consider the risks and benefits. 

Chin offers the following exercise:

Three Questions to Ask Before Using an App


Why am I using this app?

Guidance: Clearly identify your intent and avoid giving personal data without a purpose.

Example: I want to track my menstrual cycle.


What is the benefit to me?

Guidance: Consider what the app adds to your life.

Example: I’m understanding my body better. Seeing how my appetite changes based on where I am in my cycle helps me care for myself and honor my hunger.


How does this app work?

Guidance: Research your app’s developer and learn more about the company. Find any mission and purpose statements available online. Read through the app’s terms and conditions, as well as its privacy policy.

Example: Reading my app’s terms and conditions, I realized the developer gives pieces of my data to advertisers. I’m not willing to give my information to them anymore. I’m going to delete the app and use a pen-and-paper system instead.

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How Can I Use a Period or Pregnancy Tracker Safely?

For women who decide to use an app to track their sexual and reproductive health, Chin proposes six questions to consider when choosing an app.

According to a 2016 Obstetrics & Gynecology study, most free menstrual cycle tracking apps do not accurately predict a woman’s cycle.

Is the app accurate?

According to a 2016 Obstetrics & Gynecology study, most free menstrual cycle tracking apps do not accurately predict a woman’s cycle. Instead of making a prediction based on the average length of a user’s menstrual cycle, many of these apps base their estimate on a default 28-day cycle, which is not accurate for all women. A healthy menstrual cycle can last 21 to 35 days.

Does the app have a privacy policy?

In a study of 184 free apps designed to help consumers manage their medications, researchers found that only 63 (34.2%) had a privacy policy—a legal document laying out a company’s data collection practices. Having one in place suggests the developers have considered how users’ data is gathered and used. A privacy policy should be your minimum standard for using an app that collects personal data.

Can you use the app without an account?

Some women’s health apps allow you to use them without creating an account. Without an account, you won’t have to provide personal identifying information, such as an email address, that could be connected to your health data.

If you have to create an account, can you set a password?

Your personal health data is valuable and worth the extra step of entering a password to secure. Look for an app that lets you create a password. Creating a strong password further protects your data. The HIPAA Journal notes that a skilled hacker can often crack a user-generated password within 10 minutes and recommends using a password management system, which encrypts passwords and makes them unusable by hackers.

Can you withhold any personal information?

One of the simplest ways to protect your data is to limit what you provide. Before filling out a form, note which entries are required and which are optional. Give as little identifying information (i.e., your last name or postal code) as possible. The fewer personal tags on your data, the more private your information will be.

Is any organization certifying the app?

You’ll find lists online of the “best period-tracking apps,” which may not be informed by experts in women’s health or data security. When evaluating an app, look for endorsements from third-party groups focused on patient health, such as the American College of Obstetricians and Gynecologists.

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An OB-GYN’s Perspective on Period and Pregnancy Trackers

Apps that track your sexual and reproductive health can be an empowering tool to prepare for appointments with your primary care provider or specialist, but they can also cause unnecessary stress.

Sara Bates King, CNM, FNP, ARNP, at MultiCare Women’s Health & Wellness Center and Dr. Jack Feltz, an obstetrician-gynecologist and president of the U.S. Women’s Health Alliance, offer advice for women to better integrate tracking apps into their lives.

Focus on the tracking options most relevant to your care.

These apps can track many variables, from energy and emotions to cravings and skin quality. Which metrics you choose to monitor depends on why you are tracking your period, said Bates-King. Women with painful periods could benefit from logging pain symptoms and their frequency, such as severity of cramps, heaviness of flow, and problems with digestion. For other women who have migraine headaches, recording when they happen in the cycle is important. For those tracking fertility, basal body temperature and the dates of unprotected intercourse are important. Even the subtle pieces, including hydration and exercise and mood, can help put together a complete picture for the provider.

“As long as the patient doesn’t feel overwhelmed, I think more information is great, and we can sort through it together.”

—Sara Bates King, CNM, ARNP

Bring what you’re learning to your provider.

Many apps have an educational component: articles, community forums and tips. Discuss what you learn and any questions with your provider, so they can make sure the guidance is medically sound. This is important even if the app’s description says the material was developed by a medical team.

“An app is only as good as the content in it. Without every app being validated by the practice, by the American College of OB-GYN, by the physician, the content is questionable.

—Jack Feltz, MD

Maintain perspective.

For women trying to conceive, tracking apps may cause unnecessary stress and fear. Knowing your “fertile window,” the date range that an app predicts you will ovulate, can create an illusion of control. If you are trying to become pregnant, try not to jump to conclusions and bring your concerns to a provider who knows you and your medical history. Put tracking apps in their proper place as a useful tool—not the final word.

“As long as we’re using the app as a tool that helps provide more information and then helps guide providers and patients in making decisions, I think it can be really helpful”

—Sara Bates-King, CNM, ARNP

Leverage your provider’s expertise.

Online resources can enrich conversations with your provider and help you ask better questions. But overly relying on apps for health advice, which may not be vetted by a true medical professional, can create more confusion than clarity.

“Google isn’t always going to tell you the right thing to do.”

—Jack Feltz, MD

With an understanding of how period- and pregnancy-tracking apps work, women can make the best decisions for their health and personal security.

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Citation for this content: Syracuse University’s online master’s in computer engineering