A collection of Tech Tip features, which answer questions about technology, tools, devices and apps in clinical practice.
Here's a new birth control app called the Natural Cycles, which claims to be "as good as the pill" at preventing pregnancy. The Natural Cycles app works by counting the time since the last menstrual period and monitoring body's temperature.
Natural Cycles app is more effective than the pill, according to the latest and largest study into the app's efficacy. After testing 22,785 women throughout 224,563 menstrual cycles, the startup found the app provided 99 percent contraceptive effectiveness if used perfectly. If used "typically", the app was 93 percent effective. The contraceptive pill, meanwhile, is 91 percent effective.
This is how it works: Around the time of ovulation, the female body temperature rises slightly (about 0.3℃) and remains slightly elevated throughout the rest of the menstrual cycle. The ova (female eggs) only live for about a day. That means that if a woman were to have sex with a man for a window of time after ovulation, she cannot get pregnant. If she has sex with a man before she ovulates, on the other hand, she can get pregnant - as sperms can stay alive in her uterus for close to a week.
The app uses an algorithm that takes into account body temperature and many other factors like sperm survival, temperature fluctuations, and cycle irregularities. That way, it can detect ovulation and fertility as well as the different stages of menstruation cycle.