Natural Cycles

Backed by science, the Natural Cycles° algorithm is powered by your body temperature.

Inside the app

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Our FDA Cleared algorithm uses your temperature to identify fertile and non-fertile days.

trackers

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Log mood, energy, and more to see how your cycle impacts you.

ovulation prediction

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Customized insights and expert content to help you understand your unique experience.

Hear directly from Cyclers like you

4.8

40K+ ratings in the App Store

Michelle

Michele

I feel empowered knowing about my body’s natural processes.

NC° Birth Control

Bethany

Bethany

I’ve experienced significantly less pelvic pain... and our intimacy couldn’t be better.

NC° Birth Control

Dr. Katara

Dr. Katara

Has got to be THE best natural birth control on the market. 10/10 recommend!

NC° Birth Control

Shadow

Shadow

NC° helped me understand my body, cycle, and the best time of the month to get pregnant.

NC° Plan Pregnancy

Katie

Katie and her family

Nothing short of amazing! We just welcomed our baby girl thanks to NC° 🥰

NC° Plan Pregnancy

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#NaturalCycles

…and this happened both for the first and second vaccine doses 💉 The change was temporary and was not seen anymore in the following cycles. For those vaccinated in the luteal phase and the unvaccinated group, there was no change in cycle length during the study period. Follow the link in our bio to read the full paper 📑🔗Seed cycling is a dietary practice that involves eating certain kinds of seeds – flaxseed, pumpkin, sunflower, and sesame seeds – during the menstrual cycle or at certain times of the month.⁠
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The rationale behind the method is that the seeds will help the body have a healthy balance between estrogen and progesterone. In turn, this is meant to help regulate the menstrual cycle and improve fertility, and it’s also been claimed to reduce symptoms of PMS, PCOS, endometriosis, and menopause.⁠
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Seed cycling itself is not new, but it has gotten more attention and become more widespread in recent years through social media and the wellness industry ✨⁠ Follow the link in our bio to learn more about how to do it & what the science says about it 🔗WAKE ME UP WHEN SEPTEMBER ENDS 🎶🍂⁠
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...jokes aside 🤭 Our Green Days are days where you are not fertile, which means that you do not need to use additional protection (like condoms) or withdrawal during sex.⁠
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Green Days will be displayed with a green circle and the text Not fertile on the Today view 💚⁠
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The algorithm will only give you a Green Day if it is certain, based on the data you have logged, that you are not fertile for that day — either by confirming that you have already ovulated or that you are unlikely to do so in the coming five days (due to sperm survival).⁠
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You may get your first Green Days as early as in your first cycle. As the algorithm gets to know your unique cycle, you will experience more Green Days. Exactly how many Green Days you get may vary from cycle to cycle and it will depend on factors such as when you usually ovulate, how much your ovulation varies and how much your temperature varies from day to day. ⁠
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You can trust the very first Green Day you are given, as long as you see it on the Today view. This means that you have to check your daily fertility status each day before having sex and not rely on previous predictions.⁠
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Keep in mind that the only method of contraception that protects against STIs is the male and female condom. Should you have a reason for concern, be sure to use them regardless of fertility status 💜⁠
⁠The short answer: 93% effective with typical use and 98% effective with perfect use, i.e. the same as if used with a basal thermometer 🌡️ Likewise, the fraction of Green Days is comparable when using Oura Ring or the oral thermometer 💚 This was shown in the clinical study that we conducted and was further validated by the FDA after reviewing our data. ⁠
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It’s important to note that using Natural Cycles perfectly means avoiding unprotected sex on days the app has identified as fertile (Red Days) ❤️⁠
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If you are interested in the long answer, follow the link in our bio 🔗

Common questions

You must be over the age of 18.Does not protect against STIs.

FDA Cleared

Natural Cycles is 93% effective with typical use, 98% effective with perfect use. No method of contraception is 100% effective. Natural Cycles does not guarantee that you cannot get pregnant, it only informs you whether and when you can become pregnant based on the information that you enter into the application.