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About Natural Cycles
Our mission at Natural Cycles is to pioneer women’s health with research and passion – by empowering every woman with the knowledge that she needs to take charge of her health.
Science is at the heart of what we do
Natural Cycles is grounded in science, from our origin story to the regulated processes we follow every day. Our in-house Medical, Algorithm, and Data Team is made up of fertility experts, physicists, and data scientists. We are constantly looking for ways to enrich the field of female health, collaborating with academics, scientists, and doctors around the world. Do you share our mission?
How does Natural Cycles work?
Natural Cycles is an app powered by an algorithm that determines your fertility status based on body temperature. Just measure, add your temperature to the app, and let our algorithm do the work.
Measure your temperature and add data
When you wake up, measure your temperature using your basal thermometer and add the reading into the NC° app.
Wait for the algorithm to calculate your fertility
Our algorithm uses temperature, period, and cycle data to quickly see if today is green (not fertile) or red (use protection).
Know your fertility and take control of your cycle
Your daily fertility status can be used to plan or prevent pregnancy. Plus, you’ll receive tailored insights into your own unique cycle.
How body temperature works
Body temperature changes during the menstrual cycle and can be used to detect ovulation and identify your fertile window.
How our algorithm works
Natural Cycles is more than a fertility awareness method. It’s powered by a regulated and certified algorithm that learns the pattern of your unique cycle to work out each daily fertility status.
Your cycle starts on the first day of your period. Ovulation happens around the middle of the cycle, but this day can change depending on the pattern of your cycle.
Sperm can survive for up to 5 days in the female reproductive system. This means you are fertile for 6 days each cycle (ovulation day and 5 days prior). This is known as the “fertile window”.
After ovulation, basal body temperature rises due to hormonal changes. The algorithm uses this temperature rise (and optional LH tests) to detect and predict ovulation.
At first, the algorithm mostly gives red days. However, as it learns your cycle and detects ovulation, it will give more green days. This science means you can trust Natural Cycles from day 1.
How to use the Natural Cycles° app
Read your daily fertility status
After adding your temperature, you will get your fertility status for the day. This is either green (not fertile) or red (use protection). If trying to prevent pregnancy, you should use condoms or abstain from sex on red days.
Track PMS, pain & more
Add optional data throughout your cycle including changes to mood, sex drive, PMS and pain. Tracking symptoms can help you learn even more about your unique menstrual cycle.
Understand your cycle
Our popular graph feature helps you identify patterns in your cycle. You can also view the symptoms you have logged. Easily compare cycles or zoom out for an overview.
Adapt your fertility journey
Natural Cycles is a long-term fertility partner. Switch between NC° Birth Control, NC° Plan Pregnancy and NC° Follow Pregnancy depending on your journey.