What Is Fertility Awareness? Fertility awareness is a way to try to prevent pregnancy by not having sex around the time of ovulation (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 Back to Articles Related Articles About Birth Control: What Parents Need to Know Talking to your kids about sex can be a challenge. But discussing issues like birth control can help lower teens' risk of unintended pregnancy or getting an STD. Read More About Emergency Contraception Emergency contraception is a way to prevent pregnancy after unprotected sex; for example, if a condom breaks or slips off during sex. Read More Questions and Answers About Sex Answering kids' questions about sex is a responsibility many parents dread. But by answering these questions honestly, parents can help foster healthy feelings about sex. Read More Talking to Your Kids About STDs Your kids need to understand how STDs spread and how to protect themselves. Here's how to talk to them about sexually transmitted diseases. Read More About Birth Control Before you consider having sex, you need to know how to protect yourself. Read this article to get the basics on birth control. Read More Fertility Awareness Learn what the fertility awareness (rhythm method) of birth control is and how it works - and some of the reasons why it might not work for teens. Read More STDs Parents should learn about the most common STDs, how they spread, and how they're diagnosed and treated. Read More Should Girls Who Aren't Sexually Active Be Vaccinated Against HPV? Find out what the experts have to say. Read More Your Daughter's First Gynecology Visit The idea of going to the gynecologist may make your daughter feel nervous. Here's how to make her feel more comfortable about a well-woman visit. Read More Female Reproductive System Learning about the female reproductive system, what it does, and the problems that can affect it can help you better understand your daughter's reproductive health. Read More Note: All information is for educational purposes only. For specific medical advice, diagnoses, and treatment, consult your doctor. © 1995-2021 KidsHealth®. All rights reserved. Images provided by The Nemours Foundation, iStock, Getty Images, Veer, Shutterstock, and Clipart.com.