What is Natural Family Planning (NFP)?

Natural Family Planning (NFP). Photo © 2015 Dawn Stacey

What is NFP?

Natural family planning (NFP) is a natural method that you can use to determine when to have sex -– either to avoid pregnancy or to increase your chances of becoming pregnant. NFP birth control methods do not require medication, physical devices, or surgery to prevent pregnancy.

So How Does NFP Work?

Natural family planning relies on your fertility awareness. During your monthly cycle, several changes occur in a woman's 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. 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 whether you are trying or not trying to get pregnant).

What Changes Do I Need to Look For?

Natural family planning methods require you to monitor and track specific changes that occur in your body. This will help you predict when you are most fertile (and likely to conceive). NFP involves paying attention to changes in your cervical mucus and basal body temperature (your baseline temperature when you first wake up in the morning).

  • 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 aren’t likely to get pregnant during this time. More mucus is made (and is often cloudy or whitish and sticky) as you are getting close to ovulation. 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 should be clear and 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.
  • Your basal temperature will rise a little bit when you ovulate. If you record your basal temperature every day, after a few months, you will have a better idea when you will be fertile. Typically, 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.

    Remember, 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.

    What Else Should I Know About NFP?

    Fertility awareness/natural family planning methods require training, commitment, discipline, and determination in order to be effective. You and your partner need to be able to communicate and cooperate with each other, and you should be in a stable, monogamous relationship.

    Why Do People Choose Natural Family Planning?

    Some couples choose NFP for religious reasons. Other people may turn to NFP because they are allergic to latex condoms and diaphragms (though there are latex-free condoms as well as polyurethane ones). Women may prefer natural family planning because they cannot use hormonal birth control.

    NFP Methods Include:

    • Standard Days Method or Calendar Method
    • Basal Body Temperature Method
    • Billings Method (tracking cervical mucus)
    • Symptothermal Method (combining several NFP methods: cervical mucus, temperature, and calendar methods)

      How Effective is Natural Family Planning?

      The average effectiveness rate of all the NFP methods:

      • Typical use: 77-88% effective
      • Perfect use: 95-97% effective
      • Of every 100 women who use one of the NFP methods, 12-23 will become pregnant within the first year (with typical use) and 3-5 will become pregnant with perfect use.

      In order for NFP to be most effective, you (and your partner) should fully understand this method and have received instruction about it. You both need to support each other, be committed to naturally 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 as well as remembering to do so.

      Has your iPhone become an essential part of your life? If so, why not use it to assist in Natural Family Planning by charting fertility?


      United States Department of Health and Human Services. (2014). "Natural Family Planning: The Facts." Accessed October 27, 2015.

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