If you’re one of the millions of women relying on a fertility app to track your cycle, you might want to reconsider.
A new study out of Georgetown University’s School of Medicine has analysed over 95 of the most popular cycle trackers and found that the majority of them are unreliable when it comes to birth control.
Over 50 of the more popular downloads for women’s fertility were discounted after researchers found that they included disclaimers which advised users not to rely on the app as means of preventing pregnancy – 10 of the apps did not attempt to predict a women’s most fertile days.
Using the remaining 30 apps researchers entered seven cycles worth of information into the data fields. This information was sourced from real women and included things like changes to cervical fluid and basal body temperature, both of which are strong indicators of impending ovulation. The team also included urinalysis results which tested for changes in LZ, a hormone which is responsible for releasing a mature egg from the ovary.
Ovulation tracking involves a women noting changes to her cervical fluid. As she gets closer to ovulation cervical fluid becomes thicker and resembles an egg white consistency. This makes it easy for the sperm to travel to meet the egg. Measuring basal body temperature is also used which spikes just before the egg is released. The hormone LZ also spikes 24 to 36 hours before an egg is released, making this a women's most fertile time for conception.