Pharmaceutical and mechanical methods for avoiding pregnancy have the highest effectiveness rates. New approaches that claim equivalent or better performance often use spotty science or dubious measurement reporting. We raised a flag when the FDA recently cleared a daily morning temperature measurement app for marketing as a family planning method in the U.S. Part of our concern was that major women’s health organizations questioned documentation supplied to the FDA. So far, apps alone and body temp readings have never been proven to be as effective for family planning as birth control pills or condoms.

Researchers at Georgetown University Medical Center (GUMC)’s Institute for Reproductive Health (IRH) recently reported interim results testing Cycle Technologie’s Dot (Dynamic Optimal Timing) fertility app. Dot uses artificial intelligence to assess fertile days based on historical menstrual cycle starting dates provided by women. The full GUMC study will track women’s use of the app for 13 cycles. The interim study, published in the journal Contraception, reported data after women used Dot for six menstrual cycles. Of 718 participants in the study, 419 women stuck with the program for six cycles. During that time there were 15 confirmed pregnancies. In each case the pregnancies occurred when participants did not use the method correctly, such as having sex on high fertility days. According to the researchers, the Dot method’s 3.5% failure rate — which includes incorrect use — is similar to the rate for birth control pills, injections, and vaginal rings.

It will be interesting to see if the pregnancy rate for women in the study using the Dot method remains low during the remaining seven cycles, although additional studies would be necessary for validity testing. The 15 women who have already gotten pregnant could have been outliers or have shared characteristics which accounted for their faulty adherence to the method. As with the other study based on daily temperature readings mentioned earlier, if a family planning method requires abstinence or using an additional method of contraception on fertile days, any comparison with a one-and-done method such as birth control pills would seem to get shaky.