Led · Equity · Feb 2023

Natural Cycles provides a direct-to-consumer contraceptive app (NC°) that uses an algorithm driven by body temperature to determine each user's daily fertility status. Users can enter thermometer readings manually or sync overnight temperature trends from an Oura Ring or Apple Watch. The app has been used by more than three million users and holds regulatory clearances in the United States (FDA), Europe (TÜV SÜD), Canada (Health Canada), Australia (TGA), Singapore (HSA), and South Korea (MFDS). Founded in 2013 and based in Stockholm, Sweden, Natural Cycles recently launched NC° Postpartum and offers multiple modes including NC° Birth Control, NC° Plan Pregnancy, and NC° Follow Pregnancy. The company plans to invest in commercial acceleration, new product development, and healthcare reimbursement automation. The business also secured a revolving debt facility as part of its recent financing. Natural Cycles develops a fertility‑tracking app and algorithm that uses body temperature and other fertility indicators to predict menstrual cycles and fertility windows. The company says its app has helped millions of women worldwide. Natural Cycles' algorithm will be integrated with Samsung’s Galaxy Watch5 infrared skin‑temperature sensor to enable overnight, temperature‑based cycle tracking. According to Samsung, the data are encrypted and stored on the device and used to power the Samsung Health Cycle Tracking feature. The skin temperature–based tracking capability is slated to roll out across 32 countries (including markets in North America, Europe and Asia) and arrive on the Galaxy Watch5 and Watch5 Pro within the second quarter. The article notes broader cautions — echoed by Apple — that temperature‑based tracking should not be used as birth control or to diagnose medical conditions and that overnight readings can be affected by factors like the sleep environment. Natural Cycles offers a subscription fertility-tracking app that uses user-input daily basal body temperature (measured to two decimals) and algorithms to predict fertile and non-fertile days, presenting results in a red/green calendar. The company includes a basal thermometer in its annual subscription and says its algorithm models individual uncertainty to adapt to irregular cycles and missing inputs. Natural Cycles reports 500,000+ users across roughly 160 countries, an average user age of 29, and a first-year renewal rate of about 60%. The team is roughly 40 people (including seven physicist PhDs) and plans to grow headcount to 100–120 within a year. The company has published studies claiming 93% typical-use efficacy and cites an oversight body–reviewed method-failure rate of 0.5% per year, but its efficacy claims have drawn criticism because it has not completed randomized controlled trials. Natural Cycles secured EU certification for use as a contraceptive in February 2017 and has applied to the FDA; planned product priorities include clinical research, product development and international expansion, with the US and UK cited as key markets. Natural Cycles offers a subscription app that asks users to input daily basal body temperature and uses algorithmic adjustments to identify fertile windows, presenting risk days with a red/green color code. The company requires manual temperature entry (a planned wireless thermometer was put on hold) and emphasizes clinical research to validate accuracy. It reports more than 100,000 active users across 161 countries and $2 million in revenue in 2015, its first full year of trading, and captured about 4% of the Swedish contraception market within 18 months. Founders Dr. Elina Berglund and Dr. Raoul Scherwitzl, a wife-and-husband physicist duo, launched the company in June 2013 and expanded from the Nordics into the U.K. in October 2014. Natural Cycles has run a 4,000‑woman study using Pearl Index metrics (typical‑use failure ~7 per 100 vs ~9 per 100 for the pill; perfect‑use 5 per 1,000 vs 3 per 1,000 for the pill) and plans more clinical work, including a randomized control study versus the contraceptive pill. The team plans to use new funding to deepen research, expand the team and push into the U.S. market while continuing to develop services around contraceptive choice and fertility.