How to Choose Your Natural Family Planning (NFP) Method

Natural family planning (NFP) is a natural method that you can use to help you decide when to have sex—either to avoid getting pregnant or to increase your chances of becoming pregnant. Other natural methods include abstinence, withdrawal, outercourse, and continuous breastfeeding/LAM.

A menstruation tracker and cell phone sitting on a desk

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In a nutshell, NFP is basically fertility awareness. It consists of different methods that help you gain knowledge about your fertility and teaches you how to read your body's natural signals to help you determine which days of the month you are most likely to get pregnant (or avoid pregnancy).

Natural family planning includes birth control methods that do not require medication, physical devices, or surgery.

How NFP Works

Natural family planning relies on fertility awareness. During your monthly cycle, several changes occur in your body. For NFP to work, you need to become aware of your body's natural functioning, so you can figure out when you are ovulating and are most fertile (likely to get pregnant).

By keeping track of the changes that take place in your body, you can plan when you should and shouldn’t have sex—depending on your NFP goal.

Each of the natural family planning methods works a little bit differently.

What Are the Different Natural Family Planning Methods?

The following are some of your NFP options:

  • Standard days method (calendar method): This method has you track the length of your cycle (usually with CycleBeads) and suggests that you not have sex during your most fertile days of the month.
  • Basal body temperature method: With this method, you use a special thermometer each morning when you first wake up to measure your baseline temperature. After logging your readings for a few months, your fertility pattern should be more clear. This can help you determine when you should have or not have sex.
  • Billings method: This method instructs you to inspect and track changes in your cervical mucus. This can be helpful because your cervical mucus changes in reliable ways throughout your menstrual cycle.
  • Symptothermal method: This method is a combination of the other NFP methods. So, you check your cervical mucus, take your basal body temperature, and track your cycle length.

Remember that sperm can live in your body for up to a week. If you have sex without any birth control up to seven days before and a day or two after you ovulate, you have a greater chance of becoming pregnant.

How Effective Is Natural Family Planning?

In order for natural family planning to be most effective, you (and your partner) should fully understand your chosen NFP method. You both need to support each other, be committed to natural family planning, and sexually abstain (or use contraception) during your most fertile times. You must also be willing to monitor and chart your fertility signs.

The average rate of effectiveness of all the NFP methods:

  • Typical use: 77 to 88% effective (reflects how the average woman uses her NFP method: not correctly or consistently each and every time)
  • Perfect use: 95 to 99.6% effective (when you always use your NFP method correctly and consistently)

This means that of every 100 women who use one of the NFP methods, 12 to 23 will become pregnant within the first year (with typical use) and five or fewer will become pregnant with perfect use.

Changes to Look For When Using NFP

Natural family planning methods require you to monitor and track specific changes that occur in your body. This process will help you predict when you are most fertile and likely to conceive. 

  • Cervical mucus: The presence, color, and thickness of your cervical mucus can tell you what changes are happening in your body. After your period ends, you should have "dry days" (with no cervical mucus). You are not likely to get pregnant during this time. More mucus is made (and is often cloudy or whitish in color and sticky) as you are getting close to the time you will ovulate. You should be abstinent at this time or use back-up contraception if you don’t want to become pregnant. Right before you ovulate, you should see the most mucus. It is usually clear, slippery, and easily spreads apart on your fingers. This is when you are most fertile. If you have sex at this time, you may want to use a condom, sponge, or female condom to avoid getting pregnant.
  • Basal body temperature: Before you ovulate, your basal body temperature is usually between 96 and 98 degrees. It will rise a little bit (typically less than one degree) when you ovulate. Because the temperature changes are so small, you need to use a special basal body thermometer, which is designed to measure more specific temperatures. If you record your basal temperature every day, after a few months, you will have a better idea of when you will be fertile. In general, you are most likely to become pregnant two to three days before your temperature rises and one day after that. Once your temperature has been higher for at least three days, your chances of getting pregnant are much lower.

Why People Choose Natural Family Planning

Some couples choose NFP for religious reasons or just as a personal preference.

You may choose NFP because you feel more comfortable using a natural birth control method that has no side effects. Some couples may turn to natural family planning because they are allergic to materials used in devices like IUDsimplantsdiaphragms, or condoms (though there are latex-free condoms, as well as polyurethane ones). 

Some women may decide on natural family planning because they cannot use hormonal birth control.

Natural Family Planning Is Not Advised for Some People

Although there are a lot of advantages to using NFP, it may not be the best birth control option for all women. There are a couple of reasons for this.

  • In the beginning, natural family planning takes a lot of time and effort every day. You need to remember to track the days of your menstrual cycle, and chart temperature and/or cervical mucus.
  • Many women do not have completely regular menstrual cycles/periods. This can make it difficult to accurately pinpoint the definite time that you are fertile each month. 
  • Your menstrual cycle can be affected by many factors. Stress or being tired or sick can cause shifts in your cycle.
  • Infections or colds that cause low-grade fevers can have an effect on your basal body temperature, so your temperatures that month may not reflect your overall fertility pattern.
  • Even though natural family planning is effective, this method may not be the best choice if preventing pregnancy is a high priority—either due to health reasons that being pregnant can cause or because you are not ready to have a baby.

Things to Consider if You're Going to Use NFP

Fertility awareness or natural family planning methods require training, commitment, discipline, and determination in order to be most effective. You and your partner need to be able to communicate, trust, and cooperate with each other.

Because NFP does not protect you against sexually transmitted infections, you should also be in a stable, monogamous relationship.

Even though natural family planning methods are typically inexpensive and do not require you to visit with your healthcare provider, you should do your research and possibly receive specialized training if you want this method to be effective.

A certified/qualified professional can properly teach you the NFP method of your choice. They can assist you in your monitoring to make sure that you are doing this the right way, and that you are correctly interpreting your body's signs and fertility pattern.

A Word From Verywell

NFP is a great and empowering natural birth control method that can be used to help you determine when having sex may or may not result in pregnancy.

Know that your first task with natural family planning is to become familiar with your menstrual cycle and to chart your fertility patterns. Be patient because this monitoring can last for several months (and have a back-up contraception plan during this time). Also, keep in mind that if you do not completely or reliably follow the instructions of your chosen NFP method, it can be much less effective.

The truth is, in practice, NFP may not be as reliable as other forms of birth control. That being said, if you are committed to tracking and recording your fertility information, you can enjoy much higher success rates. You might find mobile apps dedicated to helping you chart your fertility useful.

Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.

By Dawn Stacey, PhD, LMHC
Dawn Stacey, PhD, LMHC, is a published author, college professor, and mental health consultant with over 15 years of counseling experience.