Fertility Awareness (for Parents)
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Fertility Awareness

Reviewed by: Larissa Hirsch, MD

What Is Fertility Awareness?

Fertility awareness is a way to try to prevent pregnancy by not having sex around the time of (the release of an egg during a woman's monthly cycle). Couples who want to have a baby can also use this method to plan sex during the time the woman is most likely to conceive. Fertility awareness is sometimes called natural family planning, periodic abstinence, or the rhythm method.

How Does Fertility Awareness Work?

If a couple doesn't have sex around the time of ovulation, the girl is less likely to get pregnant. The trick is knowing when ovulation happens. Couples use a calendar, a thermometer to measure body temperature, the thickness of cervical mucus, or a kit that tests for ovulation. The ovulation kits are more useful for couples who are trying to get pregnant. The fertile period around ovulation lasts 6 to 8 days. During this time, a couple using only fertility awareness for birth control should not have sex.

How Well Does Fertility Awareness Work?

Fertility awareness is not a reliable way to prevent pregnancy for most people. Over the course of a year, as many as 24 out of 100 typical couples who use fertility awareness alone will have an accidental pregnancy.

It is often very hard to tell when a girl is ovulating. She can conceive for up to 5 or 6 days before she ovulates and 1 or 2 days after. Because teens often have irregular periods, it makes predicting ovulation much harder. Even girls who usually have regular cycles can have irregular timing of ovulation from things like stress or illness. Fertility awareness requires a commitment to monitoring body changes, keeping daily records, and not having sex during the fertile period.

Does Fertility Awareness Help Prevent STDs?

No. Fertility awareness does not protect against STDs. Couples having sex must always use condoms to protect against STDs, even when using another method of birth control.

When Should I Call the Doctor?

Someone who uses fertility awareness should call the doctor if she:

  • might be pregnant
  • has a change in the smell or color of vaginal discharge
  • has unexplained fever or chills
  • has belly or pelvic pain
  • has pain during sex
Reviewed by: Larissa Hirsch, MD
Date reviewed: November 2018