Contraception app Natural Cycles approved by the FDA

Terri Cornelison

The US regulator has cleared Natural Cycles, the first direct-to-consumer smart phone application as a form of “digital contraception” despite a number of alarms raised by its users.

The app has been developed by Swedish-based NaturalCycles Nordic AB, to help women who follow widely used fertility awareness method to prevent pregnancies.

Natural Cycles is using an algorithm that calculates the days of the month a woman is likely to be fertile based on daily body temperature inputs and menstrual cycle information.

Therefore women are required to take their temperature daily using a more accurate basal body thermometer and to enter the reading into the app, which also tracks a user’s menstrual cycle.

The application then calculates days when women are more likely to be fertile and prompts them to abstain from sex or use other protection such condoms.

Clinical evaluation of the app involved 15,570 women who used the app for an average of eight months and proved 93% effectiveness.

[caption id="attachment_45587" align="alignleft" width="80"]Terri Cornelison Terri Cornelison[/caption]

Terri Cornelison, assistant director for the health of women in the FDA’s Centre for Devices and Radiological Health, said: "Consumers are increasingly using digital health technologies to inform their everyday health decisions, and this new app can provide an effective method of contraception if it’s used carefully and correctly,"

"But women should know that no form of contraception works perfectly, so an unplanned pregnancy could still result from correct usage of this device."

A number of alarms have been raised about the app resulting in unintended pregnancies in a recent Guardian report whose author reported becoming pregnant while using it.

Because Natural Cycles requires accurate daily users input, it is prone to human error, also the app cannot warn when ovulation begins early.

During clinical trials the app had a “perfect use” failure rate of 1.8%. The app had a "typical use" failure rate of 6.5%, which accounted for women sometimes not using the app correctly by, for example, having unprotected intercourse on fertile days.

The FDA says the app shouldn’t be used by individuals for whom pregnancy would be a major risk to the mother or fetus, nor by women who are using contraception that inhibits ovulation.

The regulator reviewed the Natural Cycles app through the de novo premarket review pathway, a regulatory pathway for novel, low-to-moderate-risk devices of a new type.

Along with this authorisation, the FDA is establishing criteria, called special controls, which clarify the agency’s expectations in assuring the accuracy, reliability and effectiveness in preventing pregnancy using apps indicated for contraception.

profile mask

Piotr Wnuk