Skip to main content

Natural Family Planning

Natural family planning is a way to track your cycle to help you better understand your own fertility. It helps you determine when your body is most fertile so you can either avoid or try to get pregnant. As contraception, it can be as effective as the pill (99% effective) when followed exactly, and there are no physical side effects, like there are with hormonal birth control.

By taking your temperature with a basal thermometer, recording the length of your menstrual cycle, and keeping track of changes to your cervical mucus, you can get a good understanding of your own body’s fertility. Remember that your body’s natural rhythms can be affected by drinking, stress, and travel, so be sure to monitor those factors as well when you’re tracking. Natural family planning works best for women with regular periods, so if you’re struggling with an irregular period, try regulating it before using this method. Plan to track your cycle for 8 to 12 months to accurately determine your window of ovulation. You can use fertility charts, a calendar, or an app, like Natural Cycles or Clue, to keep track of your cycle.

Your Cycle Length

Your cycle starts the first day of your period and goes until the day before your next period starts. It can last anywhere from 21 to 40 days, though 28 days is “average.” Ovulation, or the time in which you can get pregnant, usually happens 10 to 16 days before your next period. Once you ovulate, you can get pregnant in the 2 days after; however, sperm lives for seven days, so you can also get pregnant if you have unprotected sex in the seven days before ovulation.


Your body temperature rises very slightly after ovulation. It’s best to measure your temperature with a digital basal thermometer (an ear or forehead thermometer isn’t accurate enough) first thing in the morning, before you get out of bed. You’ll know you’re ovulating if your temperature is higher for three days in a row than the previous six days.

Cervical Mucus

Check your cervical mucus by placing your middle finger into your vagina up to the middle knuckle. Expect your vagina to be dry right after your period. As your body prepares for ovulation, you’ll experience moist, sticky, white, and creamy mucus as your hormones change. Right before ovulation, your mucus will become wetter, clearer, and slipperier, indicating when you’re fertile. Your mucus will then become thicker and stickier again, and after three days, you’ll no longer be fertile.

If you track these three metrics daily, you should have a good idea of when you’re most fertile. Other indications that you may be fertile include one-sided pain in the area of your ovary and breast tenderness. Whether you’re trying to conceive or trying to avoid getting pregnant, natural family planning can be a safe and effective way for you to reach your goals!

P.S. Shop our fertility products to support you if you're trying to conceive.