Thousands of us use period apps to track our period or pregnancy.
However, a new study has found popular fertility apps have serious privacy flaws when it comes to how they use your personal data.
The study, published by UNSW, investigated 12 of Australia's most popular fertility apps and found they can have misleading privacy messages, hold your data for up to seven years after you stop using the app, and have inadequate 'de-identification measures', meaning your data could potentially be linked back to you.
"It's unacceptable that we have all these examples of fertility apps acting in untrustworthy ways with consumers' data," report author and faculty of law senior lecturer, Dr Katharine Kemp, told Mamamia.
Watch: The Mamamia team confess our most awkward period stories. Post continues below.
The study also found apps can ask for unnecessary details about you, ranging from your education level, if you struggle to pay your bills or even if you feel safe at home.
"They don’t need those details to help you keep track of your fertility," said Dr Kemp.