The use of fertility-tracking technology increased in some states after the US Supreme Court overturned Roe vs Wade despite warnings that reproduction-related data might not be secure, according to researchers at Ohio State University.

Data from surveys conducted in Arizona, Iowa, New Jersey, Ohio and Wisconsin showed that before the 2022 Dobbs vs Jackson Women’s Health Organization decision over one-third of women in those states reported using apps or web sites to track their menstrual cycles and sexual activity. In the year after the ruling, the proportion of survey participants using fertility trackers grew to almost half.

The survey samples consisted of different groups of people, so this result does not rule out the possibility some users did quit the apps to protect their personal data. The findings likely reflect an uptick in use of technologies aimed at improving women’s health in general, said lead author Emily Neiman, a clinical instructor of practice in OSU’s College of Nursing (nursing.osu.edu).

While there are still uncertainties about privacy policies related to period tracking, Neiman said, the findings may have a broader implication: the need for users to consider whether they can trust technology to predict or prevent pregnancy accurately. The survey showed fewer users were tracking fertility for the purposes of becoming pregnant, which may suggest they are more likely to be counting on the apps for pregnancy prevention.

“I think the lay person understanding of what information an app gives you and the reliability of that information is not great,” Neiman said. “I do think there are a lot of people out there recording when they have their period and relying on an app to tell them they’re not fertile so it’s OK to have unprotected sex, and they don’t want to be pregnant. And that would not be my advice.”

The research was published in the journal Contraception (www.sciencedirect.com/science/article/pii/S0010782425000034).

The use of apps and web sites to track periods and fertility is common. But the technology offerings vary widely, and the free versions of the most popular apps aren’t likely to help with charting things such as cervical mucus, basal body temperature, the position of the cervix or hormone levels that indicate ovulation is imminent, said Neiman, also a certified nurse-midwife. Technologies that improve fertility awareness accuracy tend to be expensive and time-intensive to use.

Neiman pursued the research question after seeing news coverage and social media posts following the ruling warning users they should delete their period trackers to avoid the possibility their personal data could be used against them.

“I wanted to see if that actually happened,” she said. “I did think people would be more concerned about privacy and that we might see a decrease in use. I was kind of surprised to see that it had increased. It doesn’t seem like people heeded the advice to stop using fertility trackers, and there could be a number of reasons for that. Potentially, more people are using tracking to recognise a pregnancy as early as possible so they have the most options or so they can seek prenatal care early, but there may be fewer people planning pregnancy now that there are these restrictions around abortion.”

Neiman and colleagues used data from the Surveys of Women (www.norc.org/research/projects/surveys-of-women.html), which questioned women aged 18 to 44 about reproductive health in the five states. The analysis compared the prevalence of the use of period- or fertility-tracking technologies and reasons for their use before and after the June 2022 court ruling that the constitution does not confer a right to abortion.

The study samples ranged from 2077 to 2521 before the decision and 2145 to 2,448 after. Results showed user prevalence increased overall and in all states except Wisconsin, where the prevalence was unchanged. The only change among participants’ reasons for using the technology was that fewer reported they charted fertility to improve the chances they would get pregnant.

Assuming period trackers continue to grow in popularity, Neiman said, the onus was on users to understand potential limitations of app fertility predictions fully and on clinicians to broach the subject of femtech use in conversations with patients.

“I would say that most users of the free versions of apps that are most easily accessible are just tracking their symptoms, when they have sex and the dates of their periods,” she said. “So it can give you a rough estimate of when you ovulate or when you’re going to start your period. I don’t think the necessary level of detail is there and that people’s understanding is good enough to rely on that. As providers and public health professionals, we could be doing a better job of educating around the reliability of the information they’re getting from these technologies to help people who are trying to prevent unwanted pregnancies.”

This study was supported by grants to several research centres from an anonymous donor. 

Co-authors include Abigail Norris Turner and Maria Gallo (now at the University of North Carolina) of Ohio State; Marta Bornstein of the University of South Carolina; and Megan Kavanaugh of the Guttmacher Institute.