An advert for a fertility app billed as a “highly accurate” contraceptive tool has been banned after it was ruled misleading.
Natural Cycles, an app founded in Sweden, also claimed to be a clinically-tested birth control alternative.
But the Advertising Standards Authority ruled that claims made in a Facebook ad were misleading as it decided the effectiveness of the app was exaggerated.
The Facebook advert, seen on July 20 last year, said: “Natural Cycles is a highly accurate, certified, contraceptive app that adapts to every woman’s unique menstrual cycle. Sign up to get to know your body and prevent pregnancies naturally.”
An accompanying video claimed the app, which charges £5.99 monthly or £39.99 annually, “offers a new, clinically tested alternative to birth control methods”.
The Advertising Standards Authority received three complaints regarding the app.
In a ruling, the ASA said: “In the context of the ad, the claim ‘highly accurate contraceptive app’ would be understood by consumers to mean that the app had a high degree of accuracy and was therefore very reliable in being able to prevent unwanted pregnancies.
“We further considered that the claim ‘Clinically tested alternative to birth control methods’, presented alongside the ‘Highly accurate’ claim would be understood to mean that the app was a reliable method of contraception which could be used in place of other established birth control methods, including those that were highly reliable in preventing unwanted pregnancies.”
The smartphone app, which uses a thermometer to track the user’s fertility, has been certified and marketed as a contraceptive since February 2017.
The Swedish company said the certification was based on clinical trials involving almost 23,000 women over two years.
The app’s algorithm takes into account factors such as ovulation day, cycle length and the average temperatures of different phases throughout the menstrual cycle.
It then assigns a number of green days to notify the user of non-fertile days, and red days – when the user is predicted to be fertile.
A 0.5 method failure rate meant five out of every 1,000 women who used the app for a year would get pregnant “specifically due to a falsely attributed green day”.
The app had a typical-use failure rate of 6.8, which meant 68 women out of 1,000 would fall pregnant during a year of use if the app failed, they had unprotected sex or did not use contraception on a red day.
It had a perfect-use rate of 1.0, meaning 10 women out of 1,000 would become pregnant after having unprotected sex on a falsely-attributed green day, or contraceptive methods failed during intercourse on a red day.
The trials led to claims of 93% typical use efficacy rate and a 99% perfect use rate.
The watchdog added that the “typical-use” effectiveness of the app was comparable to other contraceptive methods such as condoms, but was”significantly lower than the most reliable methods” including the IUD.
It further told Natural Cycles Nordic AB Sweden that they must take care “not to exaggerate the efficacy of the app in preventing pregnancies”.
Natural Cycles has previously defended the technology after it was linked to 37 unwanted pregnancies, according to a report in Sweden.