Birth control built around you

An FDA Cleared, non-hormonal, non-invasive way to take control of your fertility.

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Designed to keep your data safe
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Save up to 55% with NC° Annual Plan
Is Natural Cycles° right for you?

How it works

Choose a device

Use our free thermometer when you sign up. Or sync our app with your Apple Watch or Oura Ring.

Take your temperature

Use your chosen device to take your temperature right when you wake up.

Open the Natural Cycles app

The app shows you your fertility status, cycle trends, and helpful insights.

How effective are other forms of birth control?

NON-HORMONAL


Natural Cycles°

Natural Cycles App

93%

Copper IUD

Copper IUD

99%

Condom

Condom

87%

HORMONAL


Hormonal IUD

Hormonal IUD

99%

Vaginal Ring

Vaginal Ring

93%

Contraceptive Pill

Contraceptive pills

93%

Natural Cycles

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

Inside the app

Unlock

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

Track

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

Learn

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

Hear directly from Cyclers like you

4.8

57.7K+ ratings in the App Store

Join Our Community

#NaturalCycles

We don’t have any numbers on the birth control effectiveness of these citrus-based contraceptives, but they’re definitely not doctor-recommended today 😅 While it’s possible the natural acidity of a lemon might act as a kind of spermicide and kill off straggling sperm (yes, there are studies on this), the whole thing sounds a bit too… zingy for our taste 😝⁠
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Interestingly, there are some methods today, for example the vaginal gel Phexxi, that build on knowledge that acidity can affect the environment in the vagina and make it harder for sperm to swim 🛟 Phexxi isn't suitable for those with a history of UTIs and is 86% effective with typical use.⁠
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Clarke GN, et al. Sperm immobilizing properties of lemon juice. Fertil Steril. 2006;85(5):1529–30. Available from: https://doi.org/10.1016/j.fertnstert.2005.10.040⁠
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Planned Parenthood. Phexxi [Internet]. n.d. [cited 2025 May 28]. Available from: https://www.plannedparenthood.org/learn/birth-control/spermicide/phexxiHormones are chemicals produced by your endocrine system that regulate most of your major bodily functions 👤 You can think of them as messengers that are constantly traveling through your bloodstream and cell fluid with instructions that tell your organs and tissues, what to do, how to do it, and when 🗣️ These little messengers play a huge role in creating and maintaining a healthy body 💜 Follow the link in our bio to learn more about the basics about hormones, what a hormone imbalance might look and feel like, and more! 🔗it's about to be wiiiiild 🙂‍↕️⁠
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💌: jaded_don...or our tagged photos 🚲🌿🤪⁠
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We love you Cyclers 😅🫶🩸

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.