A Swedish hospital has filed a formal complaint about the ‘contraceptive app’ Natural Cycles after it was blamed for 37 unwanted pregnancies …

The app aims to track fertility cycles to work out when there is most and least risk of pregnancy. Effectively, a higher-tech form of the calendar or rhythm method – a notoriously unreliable method of contraception.

Natural Cycles claimed that its inclusion of additional data, like a woman’s temperature measured by a supplied thermometer, made it more reliable, and it was this which made it the first such app to be officially certified as a medical device by the European Union.

All the same, its effectiveness doesn’t appear to be great, with 37 unwanted pregnancies from its users in a single hospital. Swedish site SVT says that the hospital has reported the app to the country’s medicines watchdog.

Natural Cycles claimed an effectiveness of 93%, which is similar to that of condoms, though below other methods like the coil.

The 37 unwanted pregnancies come from a selection of 668 women who sought abortion at Södersjukhuset from September 2017 until the end of the year. We should look back to see if there are earlier cases.

Exactly why the app did not work is unclear. The Swedish Medicines Agency is now launching a study of Natural Cycles.

The company additionally told us that the stat needed to viewed in context.

“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.”

Via The Verge