A federal agency has approved an app that analyzes a woman’s basal body temperature and identifies when ovulation has occurred.
The Food and Drug Administration has cleared the app as a method of contraception to prevent pregnancy. Called Natural Cycles, it leverages an algorithm that calculates fertile days when protection or abstinence is required.
Intended for use in pre-menopausal women aged 18 and older, users measure their basal temperature in the morning—five values per week are recommended—and then enter the data into the app, which gets to know their individual menstrual cycle. With one to three cycles of measurement, the app has enough data to confirm when ovulation has occurred and accurately predict fertility.