Physicist Invents App That Can Replace Hormonal Birth Control Physicist Invents App That Can Replace Hormonal Birth Control

Physicist Invents App That Can Replace Hormonal Birth Control

by Elfy Scott Jul 24, 2019

While this year may represent the 57th anniversary of the combined oral contraceptive pill’s market availability in the United States, the mounting concern for its side effects in women’s bodies in recent years has culminated in immense pressure for researchers to develop safer and more convenient contraception options.

The media has repeatedly latched onto claims of future development of birth control products such as the remotely-controlled microchip, the male pill, or fertility-regulating vaccines, while women are still left waiting for these alternatives to hit the shelves and struggling with the side effects of out-dated contraceptive methods. However, one product currently available for purchase is proving extremely promising and attracting a great deal of attention, partly for its effectiveness but also because it requires little more than the use of a smartphone.

Natural Cycles is a birth control app launched by Swedish nuclear physicist Elina Berglund, that works by employing an algorithm to predict days of a woman’s ovulation and fertility using daily temperature readings. Following ovulation, progesterone increases a woman’s body temperature by 0.45 degrees Celsius and the app uses the tracking of daily temperature differences by comparing them against a dataset. When Natural Cycles determines that it is safe to have unprotected sex on any given day, it will give a green rating to days on the calendar, and when the app predicts that conception is likely, the days will be marked red.


Berglund, who originally worked as part of the team which discovered the Higgs Boson particle, began to work on the app in 2012 with her partner Raoul Scherwitzl, and first developed the algorithm for personal use because she wanted to “give her body a break from the pill”. Now, she states her aim is to “empower every woman worldwide with knowledge about her body, menstrual cycle and fertility” using Natural Cycles. The app is utterly unique in birth control for its ability to prevent pregnancy, as well as provide women who wish to conceive with scientific information about the days that conception is most likely to occur. Berglund herself can attest the efficiency of the app. After using it for 18 months as birth control and deciding to try for a baby, she states that she fell pregnant on her first red day.

Perhaps understandably, the Natural Cycles program initially received a great deal of skepticism, including an email from the Swedish Medicinal Products Agency demanding that the creators cease all claims of contraception until the launch of an investigation, and headlines claiming that the app was attempting to trick young women. These controversies ultimately resulted in a dramatic decline in the company’s revenue, with losses of over 50% of their users. However, last month Berglund’s app achieved the position of becoming the first app to be officially approved for use as contraception, after approval came from one of the certification bodies of the German Department of Health. While women may be apprehensive to trust the algorithm with the state of their bodies and fertility, the two clinical trials conducted with Natural Cycles found that amongst 4,000 women aged between 20 and 35 years-old, 143 had unplanned pregnancies over the course of the year with the use of the app, and only 10 of these pregnancies occurred after having intercourse on a ‘green day’. These trials have shown that the app achieves a 99.95 percent efficacy rating when used correctly (precisely the same as the combined oral contraceptive pill). With these results, Berglund can confidently claim that the app is a “natural alternative to the pill – with no side effects” and is now looking to discuss the possibility of providing Natural Cycles as a form of free contraception to UK citizens under the NHS. Currently, the app has 100,000 users worldwide and charges £6.99 per month.


However, due to the amount of personal responsibility that users must assume when using the app in regards to daily temperature readings, researchers have suggested that Natural Cycles is not the best option for all women. Kristina Gemzell of the Swedish Medical Institute has stated that the efficacy of the app is still not equal to that of intrauterine implants and should not be recommended to very young women or those “keen to avoid pregnancy”. Despite this, the app’s developers have asserted that they do not advertise to teenagers and state that the app would be most ideally suited to women 20 to 35 years-old who are currently in a relationship, and able to use the program effectively.