Swedish authorities have completed their assessment of a ‘contraceptive app’ after a hospital discovered a number of unwanted pregnancies among women who relied on it.

Natural Cycles was referred to Sweden’s Medical Products Agency (MPA) after claims that 37 out of 668 women seeking an abortion at one of Stockholm’s largest hospitals from September to December 2017 were relying on the app as a method of contraception.

In response, the MPA asked Natural Cycles to clarify the risk of unwanted pregnancy in the instructions for use and in the app, which last month received clearance by the Food and Drug Administration (FDA) in the US.

The company was also asked to make some updates to the procedure for tracing and handling of software versioning.

Natural Cycles was able to demonstrate that these changes had already been implemented earlier this year.

Another part of the investigation involved the MPA reviewing the product’s performance when used in Sweden.

This included looking into the number of registered users, the number of active users and the number of pregnancies.

The outcome of this investigation revealed the number of pregnancies was in line with the published typical use effectiveness rate for Natural Cycles (93%), which is based on a study of over 22,000 women.

This meant the MPA declared its assessment complete, with no further action required by the company.

Raoul Scherwitzl, Natural Cycles CEO, said the company was ‘pleased’ that the process had  concluded.

He added: “There has been a lot of discussion about this investigation, and we hope that it will provide some reassurance to women to see eminent bodies like the Swedish MPA and the US FDA in alignment based on the strength of our clinical evidence.

“We never doubted the effectiveness of our product since the number of reported pregnancies is monitored closely on a monthly basis – this is an ongoing responsibility that we commit to as part of operating in a regulated environment.”

Natural Cycles uses algorithms to determine ‘red’ or ‘green’ days, which indicate whether a woman is at risk of pregnancy in the event of unprotected sex on a specific day.

Women must take their temperature at the same time every morning to allow the app to track ovulation and menstrual cycle phases.

But in August 2018, a Facebook advert for the app was banned after the Advertising Standards Agency (ASA) ruled it to be misleading.

Complaints made about the advert, which claimed the app was ‘highly accurate’, were upheld by the ASA on the grounds they were ‘misleading’.