Natural Cycles became the first and only app to receive FDA clearance as a method of birth control. The app contains an algorithm that calculates the ‘fertile window’ based on basal body temperature (BBT) and menstrual cycle information. It makes the women aware of her ‘fertile days’ to avoid sex or use a barrier method if practicing birth control.
Terri Cornelison, M.D., Ph.D., assistant director for the health of women in the FDA’s Center for Devices and Radiological Health said in a press release, "Consumers are increasingly using digital health technologies to inform their everyday health decisions, and this new app can provide an effective method of contraception if it’s used carefully and correctly."
"But women should know that no form of contraception works perfectly, so an unplanned pregnancy could still result from correct usage of this device," she added further.
“Natural Cycles can adapt to each woman’s body and, with a high degree of precision and accuracy, determine when she is ovulating,” says Dr. Elina Berglund, a physicist who created the app along with her husband Dr. Raoul Scherwitzl, a postdoctoral researcher.
Natural cycles is just like old times period tracker with some added features. The app requires the women to input her daily basal body temperature recordings and the date of menstruation. LH test result is an optional entry point.
The app’s calendar then labels fertile days as red (when you should abstain or use a condom) and the rest green, when you are “safe.” Using the sensitive thermometer and some mathematics the app claims itself “as good as the pill" at preventing pregnancy.
The app is primarily based on the fact that a woman’s body temperature rises slightly (about 0.4℃) after ovulation and remains slightly elevated throughout the rest of the cycle. The app uses an algorithm that considers body temperature, cycle irregularities, sperm survival, length of menstrual cycle and cycle irregularities. The algorithm learns from previously recorded cycles from the same woman and can provide predictions of her fertility status and upcoming ovulation, LH and menstruation days.
Initially, the app shows a nearly equal number of a green and red day but, as women continue using the app and fed more data, the number of red days is reduced to 8 each month. The app is 99.95% sure before it assigns a day red or green. If in doubt it will go red.
Clinical studies involving 15,570 women found that when used correctly, the failure rate for the app was 1.8%, while with typical use, or women sometimes not using the app correctly, the failure rate was 6.5%. "Based on the strength of our clinical data, we are delighted that the FDA granted De Novo classification for Natural Cycles and look forward to working together with healthcare professionals to offer a digital form of birth control to women in the US," said Elina Berglund.
"Our mission at Natural Cycles is to pioneer women's health with research and passion, and this milestone marks a very important step in that journey."
Anyone can use it, even women with PCOD or irregular cycles, only these women will have more red days on the calendar than green. Natural Cycles is contraindicated in women in whom pregnancy poses a serious risk to mother or fetus or in those who use other forms of contraception that prevent ovulation. The method also does not prevent STIs.
The Natural Cycles app can be purchased through the Apple store or Google Play on a yearly subscription basis for $79.99 a year (includes oral basal thermometer) or monthly for $9.99 per month. They also offer a free trial period of 1 month.
Here is a video about Natural Cycles app for healthcare professionals.
