Many years ago (in the BC era, that is, before computers, mobile phones and apps) religious women used to count the days between periods to determine when it was safe to have sex, away from ovulation (which imprecisely happens around the middle of the cycle) in order to avoid pregnancy. It didn’t. It was affectionately called “the Vatican roulette”.

Unfortunately in the technological era it was inevitable that many people would be attracted to an update on its predecessor, with a few improvements, like taking the body temperature (and including it in the magic tech word “algorithm”), which of course does not need an app, anybody can check one’s body temperature to increase the chances of pregnancy, if that is the effect sought, not so good to avoid it.

As reported in The Verge

“Natural Cycles, a contraceptive app that became certified in the EU as a form of birth control, has been hit with a complaint after being blamed for causing 37 unwanted pregnancies, reports Swedish agency SVT. Södersjukhuset hospital in Stockholm reported the app to Swedish regulator MPA (the Medical Product Agency), after 37 women visited the hospital for an abortion after becoming pregnant while using Natural Cycles.

“The app uses an algorithm and measures factors like temperature to determine the period when a woman may be fertile. It’s a popular alternative to hormonal contraceptives like the pill because it lacks side effects. In a statement to The Verge, Natural Cycles said it hasn’t received any information from Södersjukhuset hospital, but it is in touch with the MPA about each individual case. The company has also initiated an internal investigation with their clinical department, and said:

“No contraception is 100% effective, and unwanted pregnancies is an unfortunate risk with any contraception. Natural Cycles has a Pearl Index of 7, which means it is 93% effective at typical use, which we also communicate.

“At first sight, the numbers mentioned in the media are not surprising given the popularity of the app and in line with our efficacy rates. As our user base increases, so will the amount of unintended pregnancies coming from Natural Cycles app users, which is an inevitable reality.”

In the UK an National Health Service website asks serious questions about the validity of the research into the app and its claims.

Apps are great money-makers and high tech lends a semblance of certainty to things which are anything but. There is a need for much more independent research (eg prospective comparative studies with well proven methods) to discover if this type of technology is of any use.