The Billings Method of Birth Control

The Billings method is a form of natural birth control that's also referred to as the Billings ovulation method, ovulation method, or cervical mucus method. This method of contraception is a type of fertility awareness method (FAM) birth control in which individuals learn how to recognize their own fertility patterns, so they can choose when to avoid sexual contact (to prevent pregnancy) or have sexual contact (in the attempt to conceive).

Pregnancy test on top of a calendar
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How It Works

The Billings ovulation method is based on your close assessment of your cervical mucus. Generally speaking, over the course of each menstrual cycle, cervical mucus changes in predictable ways. Usually, cervical mucus becomes clear and elastic about six days prior to ovulation, due to the influence of estrogen. Ovulation is likely to occur on the last day that cervical mucus has these features.

After ovulation, cervical mucus is affected by progesterone and becomes thick, sticky, and opaque.

What This Method Teaches You

The Billings ovulation method teaches you to identify the fertile phase of your menstrual cycle. When you learn this method, you can track your individual fertility pattern by analyzing your cervical mucus each month.

Learning to consistently observe your secretions and evaluate them is critical for this method. You would start by paying attention to your secretions several times per day.

To effectively use this method, you would take a cervical mucus sample by hand every day and record its quantity, appearance, and feel (as well as noting any other fertility/physical signs) on a daily chart. Your cervical mucus can be described as dry, watery, sticky, creamy, watery, or egg-white like— depending on where you are in your cycle.

Four Billings Method Rules

Below is a summary of the four Billings Method rules to follow for natural conception, but anyone considering this method should refer to the actual rules, which include more detailed instruction.

As per the Billings method, there are three early day rules and the peak rule:

  • The early day rules have to do with the days leading up to ovulation. During this time, the characteristic changes of your cervical mucus will correspond to the beginning of your fertile phase. The peak rule applies once the peak day (ovulation) has been identified.
  • The peak day is the last day of "lubricative sensation" and occurs extremely close to the time of ovulation. According to the Billings ovulation method, you may be fertile for another three days after your peak day, and menstruation should occur 11 to 16 days later.

Couples may choose to use a barrier method, such as condoms during the fertile period.

The Billings ovulation method doesn’t require any form of rhythm counting, temperature taking, hormonal drugs, or devices. It allows couples to share in the responsibility of natural family planning but requires cooperation and careful observation. It's also sometimes chosen for religious reasons.

The method's proponents say this natural birth control method can be used from puberty to menopause, and while breastfeeding, and for those who don’t have regular menstrual cycles.

When Can't the Billings Method Be Used?

The Billings method cannot be used with hormonal contraception (like the pill) because these birth control methods affect the hormones that alter natural signs of fertility, like cervical mucus. When you begin the Billings method, it is best to abstain from sexual intercourse until you learn to assess your cervical mucus characteristics because you may confuse sperm and/or seminal fluid with cervical mucus.

It is important to note that using fertility awareness to prevent pregnancy does not protect against sexually transmitted infections (STIs), including HIV.

It is essential that you have accurate knowledge and training of this natural birth method before relying on it to prevent pregnancy. The success of the Billings method is greatly dependent upon proper teaching, correct understanding, accurate cervical mucus observation, daily charting, mutual motivation, and cooperation between the couple.

It's important to note that your physician may not be familiar with this method. A 2017 study found that medical schools do not always include FAM as part of the OB/GYN curriculum, and many physicians are not trained in how to teach these methods. You can get a formal instruction plan by using an accredited Billings ovulation method teacher.


According to clinical guidelines published in 2018, the unintended pregnancy rate after a year of perfectly using the Billings method varies from 0.4% to 5%. In common practice, though, it's as high as 24%.

That's less effective than the pill and many other commonly used methods of birth control, such as intrauterine devices (IUDs), Nexplanon implant, or Depo Provera (birth control shot).

The authors of the research suggested using the Billings method only when an unexpected pregnancy could be acceptable. They also suggest that couples who use this method should be aware of how to obtain emergency contraception.

Bottom Line

The Billings method of birth control is a type of natural family planning in which a person learns to track the changing features of their cervical mucus to predict ovulation. This and other FAM birth control can be used to help prevent pregnancy and to predict ovulation when someone wishes to conceive.

Methods such as the Billings method do not work for everyone, and their effectiveness is generally lower than any of the commonly used forms of birth control, such as the pill or an IUDs.

If it won't feel like the end of the world if you accidentally become pregnant, a strong advantage of this type of family planning is that there are no side effects, and you can use what you've learned when you wish to plan rather than prevent pregnancy.

8 Sources
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.
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  2. Billings Life. The 4 simple rules of the Billings Ovulation Method.

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  4. FACTS: Fertility Appreciation Collaborative to Teach the Science. Billings Ovulation Method.

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  6. Danis PG, Kurz SA, Covert LM. Medical Students' Knowledge of Fertility Awareness-Based Methods of Family PlanningFront Med (Lausanne). 2017;4:65. doi:10.3389/fmed.2017.00065

  7. Centers for Disease Control and Prevention. Effectiveness of family planning methods.

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Additional Reading

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.