As SVT reports, Stockholm's Södersjukhuset hospital saw 37 women fell pregnant while using the app as a contraceptive in 2017. Midwives at Stockholm's Södersjukhuset reported the app to the Medical Products Agency after the ‘accidental’ pregnancies.
Natural Cycles tracks the changes in a woman’s body temperature over their menstrual cycle to predict days with the lowest risk of pregnancy.
As the Mail Online reports, the app’s creators have attested it is as effective as the contraceptive pill. A study from September of 22,785 women found the app was 93 per cent effective in preventing pregnancies.
"No contraception is 100 per cent and unwanted pregnancies is an unfortunate risk with any contraception,” Natural Cycles told Mail Online in a statement.
"To have 37 unwanted pregnancies out of the 668 mentioned in this study at Södersjukhuset means that 5.5 per cent of women who stated they used Natural Cycles also had an unwanted pregnancy.
"This is in line with what we communicate as the risk of unwanted pregnancy with typical use, and which is comparable to other types of contraception.”
This article originally appeared on marie claire