Natural Cycles | Contraception app sparks debate

The application Natural Cyclesapproved as a contraceptive method by Health Canada, is causing concern. What is this digital product and why do women choose to use it? Decryption.

What is Natural Cycles ?

Natural Cycles is the “only digital product that is a medical device for contraception,” explains the app’s co-founder and CEO, D^D Elina Berglund Scherwitzl. On its website, the app is described as “a non-hormonal, non-invasive way to take control” of your fertility. Health Canada approved the digital product as a contraceptive method last December, a few years after the U.S. Food and Drug Administration (2018).

In May, the Society of Obstetricians and Gynaecologists of Canada (SOGC) took a position¹ regarding the application and its effectiveness. She warns in particular that there are no studies on Natural Cycles which was carried out in Canada and compared it to hormonal contraceptives “in the context of scientifically rigorous clinical trials”.

How it works ?

The algorithm of Natural Cycles relies on data like basal body temperature to try to predict ovulation and when users are fertile. Basal temperature can be taken using a thermometer, an Apple Watch, or an Oura Ring, a smart ring that collects health information.

With the thermometer, it is necessary to take your temperature yourself as soon as you wake up, “four to five days a week,” specifies Dr.^D Berglund Scherwitzl, while the data feeds itself into the app with an Apple Watch or Oura ring. “On days when you are fertile or could be fertile, you get a red day and you have to use protection if you want to avoid pregnancy,” says Dr.^D Berglund Scherwitzl. “Green days” are given when the algorithm considers that the user is not fertile.

The subscription to Natural Cycles in Canada is sold at $13.99 per month or $99.99 per year.

Why is the app at the heart of controversy?

In a report published at the end of July, Radio-Canada revealed that Health Canada had approved Natural Cycles without requiring the company to prove its effectiveness by submitting “evidence-based data”². He reports in particular the case of a woman who became pregnant while using the product.

The approval was granted “on the basis of an attestation by the manufacturer that this medical device meets all applicable safety and effectiveness requirements,” Health Canada defends itself in an email obtained by The Press. “The manufacturer of the application Natural Cycles did not have to submit evidence to Health Canada for review, as it was not required in this case.”

“The approval process of Natural Cycles by Health Canada was no different than that of other medical devices. [même classe]such as condoms,” Natural Cycles communications manager Lauren Hanafin said in an email to The Press. Natural Cycles has notably submitted to Health Canada its instructions for use “which provide a detailed overview of the product as well as a complete summary of the clinical studies demonstrating effectiveness,” she adds.

“Seven of the thirteen articles in the literature review for this statement were funded by Natural Cycles or were written by Natural Cycles employees, which may bias the conclusions of these articles,” the SOGC warns in its position statement.

Is the app effective? Why are experts worried?

Natural Cycles would be effective “at 93% in the context of normal use, which means that 7 out of 100 women per year become pregnant,” says Dr.^D Berglund Scherwitzl. Which would be similar to the birth control pill, but superior to condoms. The effectiveness would rise to 98% with “perfect use”, which means abstaining from any unprotected sex on a red day, specifies the CEO.

“The limited data we have suggest [que les méthodes de contraception fondées sur la connaissance de la fertilité comme Natural Cycles] are no more effective than available hormonal contraceptives in protecting against unwanted pregnancies,” explains Dr.^D Céline Desjardins, retired obstetrician-gynecologist and member of the SOGC committee who took a position.

The SOGC “believes that independent studies are needed to validate the app’s claim to have a similar effectiveness rate to the birth control pill,” according to its website.

The D^D Desjardins also points out that in 2024, 50% of pregnancies in Canada will still be unplanned. Long-acting methods, such as the IUD or implant, are the closest to “perfection,” since they are contraceptive methods for which there can be no forgetting. Stress can also have an impact on the menstrual cycle and “play tricks,” she adds.

Additionally, the app states that one month of menstrual cycle tracking is enough to use it with confidence, but the D^D Desjardins instead advises following at least six cycles before using a method like Natural Cycles. Since not all women have a regular menstrual cycle, the risk remains high, after one month of use, “that pregnancy can occur, especially if the woman does not use a barrier method of protection such as a condom, and this, during all sexual activities during this entire cycle,” she explains.

“Any method of contraception, as long as it is the one that best suits the person who wants to use it, has risks and benefits,” says Dr.^D Geneviève Bois, a family physician who mainly practices women’s health. “It all depends on our level of risk tolerance.”

The D^D Bois points out, however, that “a large part of marketing [de Natural Cycles] seems to be done by paying influencers on TikTok.” She says that “it’s difficult as a doctor [de voir] that people get their healthcare information from TikTok, where the quality and diversity of information found is sometimes extremely problematic.”

What do you say about it? Natural Cycles ?

According to the D^D Berglund Scherwitzl says the app uses “complex statistical methods to determine the differences between stress and sleep, on the one hand, and ovulation, on the other.” The co-founder also points out that the algorithm makes no assumptions about a woman’s cycle, takes into account past hormonal contraception use, and does not grant green days until ovulation occurs.

As for marketing, the CEO replies that she “doesn’t think there’s been a lot of marketing done on Natural Cycles on TikTok in particular.”

Why do women use Natural Cycles ?

Alycia Rodrigue, a 23-year-old student from Quebec, uses Natural Cycles for two years and she bought the Oura ring six months ago. “When I had the thermometer, I had a lot more [jours rouges] in the app, which said to use protection,” she says. Having been using it for a while, she says the app is very aware of her menstrual cycle. She also likes that the platform informs her of symptoms she might experience throughout her menstrual cycle, such as migraines.

For her part, Joanie Cyr, a 28-year-old tattoo artist from Saint-Jérôme, has used the digital product for the past year and a half, both as a method of contraception and to plan a pregnancy. “The application really tells you that from such and such a day to such and such a day, you are at risk of getting pregnant,” which she finds practical given that women are not always fertile, she explains. Before getting pregnant, she took her temperature with the thermometer, which she considers “extremely precise,” since it is to two decimal places.

Joanie Cyr says she is aware, however, that the use of Natural Cycles carries risks. She would recommend it less to a single person without a stable sexual partner.

1. Consult the SOGC position statement

2. Read the Radio-Canada report