Thinking of ditching your pill for a different form of birth control? This app may be your answer. Natural Cycles is first app classified as a medical device for contraception, BuzzFeed reports. It works by analyzing data about the user, such as cycle irregularities and changes in temperature, to predict ovulation. “The thing about the female egg is that it only lives for about 24 hours," Dr Susan Walker, a senior lecturer in sexual health at Anglia Ruskin University, told BuzzFeed. "So if you could reliably know when you’ve ovulated as a woman, and then you give that egg two or three days to die, any time after that in the cycle you will not get pregnant because there’s no egg to fertilize." But if you're considering a switch because a hormonal pill is too much of a hassle, Natural Cycles won't work for you. The app requires users to take their temperature every morning as soon as they wake up, using a thermometer that measures to at least two decimal points. Slight changes in temperature indicate hormone fluctuations that can predict ovulation, but these differences are so small that a normal fever thermometer won't read them. After a few months of readings, Natural Cycles maps out green days and red days for users. Green means risk of pregnancy after unprotected sex is low and red that risk is high and users should consider either abstaining or using protection. A study of more than 4000 women using Natural Cycles found that only 7 in 100 got pregnant over a year when using the app how they expect most will, meaning the participants may have forgotten a day of temperature reading every once in a while. Although there is some science backing up Natural Cycles, the research was conducted by the company itself and therefore must be taken with a grain of salt. Sexual health groups warn that being classified as a medical device doesn't guarantee that Natural Cycles will effectively prevent pregnancy and call for more research independent of the company that built the app, according to BuzzFeed. Still, if birth control methods such as hormonal pills or an IUD just aren't working for you, natural family planning via apps like Natural Cycles coupled with alternative protection on your "red" days could be just what you're looking for. And hey, we're all for giving all vulva-havers even more agency over their bodies.