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Apple Stands to Revolutionize Period Tracking — If It Doesn’t Mess Up

A lot is riding on how much the company is willing to share with the public

DDr. Sumbul Desai, vice president of health at Apple, was met with cheers on Monday during the company’s Worldwide Developers Conference when she announced the tech giant had created a service specifically for monitoring menstrual cycles.

“This one is for you,” Desai said, addressing the women in the crowd. “Cycle Tracking.”

“Knowing more about your menstrual cycle gives you a window into your health, from simply ensuring you’re prepared to understanding your personal patterns and regularities,” she added.

For now, the service is available only to developers, but it’s scheduled for a full consumer release with watchOS 6 this fall. Apple Watch and Apple Health app users will then have the option of inputting data about their menstrual cycle history, such as the date of their last period, length of cycle, and symptoms. The service will use this information to make period cycle and “fertile window” predictions for the user.

“We have very limited information about how Apple intends to proceed.”

Those cycle predictions will alert women when their period is about to start. Fertile window predictions will tell women, based on their health data, which six days in a month they’re most likely to be fertile. (A footnote in Apple’s watchOS 6 press release notes “fertile window predictions” — otherwise known as the rhythm method — “should not be used as a form of birth control.”)

“We are so excited to bring more focus to this incredibly important aspect of women’s health,” Desai said at WWDC.

But not everyone is sold on Apple’s entry into reproductive health.

“We have very limited information about how Apple intends to proceed,” says Chelsea Polis, a senior research scientist at the Guttmacher Institute, a nonprofit research group that focuses on reproductive health. Polis notes it’s difficult to understand how accurate Apple’s Cycle Tracking app is without understanding the algorithm the tech company is using to predict upcoming periods and fertile windows.

“This could be the beginning of a disaster or an opportunity to lead, by ensuring appropriate testing, communication, and education of the public regarding how to appropriately use this technology,” Polis says.

It remains to be seen how transparent Apple will be about the workings of its prediction algorithm. The company didn’t immediately respond to a request for comment, although it provided some background information about the cycle tracking service.

Polis, who describes fertility as “a field that has a lot of misunderstanding and misinformation and confusion,” says she’s concerned about Cycle Tracking’s fertile window feature. She points to the do-not-use-as-birth-control footnote on the press release as an opportunity for Apple to be more transparent.

“I’d prefer it to be in flashing lights,” Polis says of the birth control footnote. And while some menstrual tracking apps are intended to prevent pregnancy, vague and misleading recommendations about how women are supposed to use their period tracking apps has been a problem among Cycle Tracking’s existing competitors.

Cycle Tracking on the Apple Watch

“Generally speaking, there are a number of other apps and devices walking in this very gray, fuzzy area of not being clear what the device is approved for use for,” Polis says. This gray area can be dangerous when it comes to health apps in particular. In the case of a period tracking service, a woman could try to use it as birth control and put herself at risk for unintended pregnancy.

Other app companies have run afoul of reproductive health experts for their misleading marketing practices. Daysy, a $330 thermometer and accompanying period tracking app, which is manufactured by the Swiss Company Valley Electronics, claimed it could predict a woman’s fertile window with 99.4% accuracy, according to a study published in the journal Reproductive Health in 2018. Last month, however, the journal retracted the study and issued a statement explaining “fundamental flaws in the methodology” meant “the conclusions are unreliable.”

It’s impossible to say whether it will improve, or threaten, women’s reproductive health.

“I worked for an entire year to get a company to clean up its act,” says Polis, who spearheaded the pushback against Daysy’s marketing. Still, the damage was done. The device was already sold around the world, including on Amazon.

Without information about how Apple plans to market Cycle Tracking, it’s impossible to say whether it will improve, or threaten, women’s reproductive health.

Onstage at the Worldwide Developers Conference, Desai called attention to the scope of Apple’s reach. “Because we wanted to make this available to hundreds of millions of women around the world, cycle tracking is also available without a watch in the Health app in iOS,” she said.

With those hundreds of millions of existing customers, Apple is positioned to change the way women understand their menstrual cycles. Of course, this also means the company has the responsibility to avoid widespread confusion stemming from the information it provides. Here’s to hoping they take that responsibility more seriously than their predecessors.

More WWDC on OneZero:

This article has been updated to clarify that Apple provided some additional product information on background.



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