Technology has seeped into nearly aspect of life, including health, which means millions of women use apps to track their menstrual cycles just as they use them to track train schedules.

But according to the Washington Post, the information entered into certain brands of those apps could make the users’ personal information easily hackable by either vindictive individuals or even just market research-minded companies.

The concern is especially connected to one application, called Glow, which Consumer Reports says has serious security flaws that allow information such as menstruation, fertility windows and whatever other reproductive or sexual information women enter into the app to be accessed by outsiders. The information isn’t necessarily protected by HIPAA. Plus, the benefits of using the apps in the first place might not be as helpful as the users believe.

Check out the Washington Post to see what other cyber risks these apps could put women in and some suggestions of how to fix them.