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Not your grandmother

Not your grandmother's guide to fertility awareness methods

5 min read

This article was last updated on May 25, 2022.

“I want to be proactive about contraception, so I rely on fertility awareness methods,” says Sam Oberlin, a 32-year-old financial analyst in Atlanta, Georgia. I diligently track my cycle and take my temperature, then record this information in my tracking app. Based on these markers, I know what days I’m fertile. This is when my partner and I use condoms.”

While intrauterine devices (IUDs), patches, sterilization, pills, and implants offer more contraception options than ever before, our temperature, cervical mucus, and menstrual cycle are natural tools that can also prevent pregnancy. These fertility awareness methods (FAMs) are perhaps the oldest forms of birth control. Today, FAMs are experiencing a modern-day makeover due to apps and devices from innovative companies. Individuals like Oberlin have the ability to more effectively use a contraceptive method that aligns with their unique needs.

So what are FAMs and how can they be used effectively? We created this guide to help you learn more about FAMs and how they stack up against other methods of birth control.

An overview of common fertility awareness methods (FAMs)

The temperature FAM

Your body’s temperature naturally shifts during your cycle. During the beginning of your cycle— before ovulation—an average person’s temperature is between 96 and 98 degrees Fahrenheit. After ovulation, this temperature rises to 97 to 99 degrees Fahrenheit. Though this change is small, it’s an important sign of fertility.

Experts at Planned Parenthood write, “Safe days to have sex begin after the increase in your temperature lasts for at least three days, and end when your temperature drops just before your next period begins. During your safe days, you can have unprotected vaginal sex. On your unsafe (fertile) days, avoid sex or use another method of birth control.”

The cervical mucus FAM

Just as your temperature shifts during your cycle, your cervical mucus does, too. For a comprehensive overview of this, check out this explanation from the American Pregnancy Association (APA). Here’s the short and sweet version: “As you approach ovulation, your estrogen levels begin to surge, which causes your cervix to secrete more cervical mucus that is of a so-called ‘fertile quality.’ This fertile-quality cervical mucus, also known as egg white cervical mucus (EWCM), is clear and stretchy, similar to the consistency of egg whites, and is the perfect protective medium for sperm in terms of texture and pH.”

Keeping an eye on your cervical mucus, whether by inserting clean fingers into your vagina or inspecting toilet paper or your underwear, is another way to gauge when you’re most or least likely to get pregnant.

The calendar FAM

The calendar method gives you insight into the days you’re fertile by recording the length of your menstrual cycle each month. After a few months of tracking, you’ll have data to better predict when you’re fertile or infertile. Check out this explanation to dive into the nitty gritty, including the math equations required to determine the “safe” and “unsafe” days for unprotected intercourse.

Teamwork makes the contraception dream work

The FAMs described above are most effective at preventing pregnancy when used together and performed assiduously. According to data from Planned Parenthood, FAMs are about 76 to 88 percent effective, depending on which FAM is used (and how carefully it's tracked).

However, when FAMs are used in conjunction with each other, this rate improves. While some optimistic studies find the effectiveness of using temperature and cervical mucus FAMs simultaneously to be 99.6%, more commonly reported stats range anywhere from 2% to 25% for typical use. This means that while FAMs are more effective when used together, they aren’t quite as effective as long-acting reversible contraceptives or shorter-term hormonal contraceptives.

Fortunately for those interested in FAMs, you don’t have to print charts off the Internet or create a daily finger painting of your cervical mucus, all while taking your temperature. While our grandmas may have gone to some of these lengths, new technological innovations (from wearable devices to tracking apps)  make it easier to track multiple FAMs.

Who doesn’t love a good pro and con list?

Here are a few key pros and cons to think on when considering if FAMs are right for you:

  • Pro: FAMs are totally natural—there are zero internal devices or hormones used.
  • Pro: FAMs help you get more in tune with your body and cycle.
  • Pro: FAMs can be effective at preventing pregnancy if they’re used perfectly and if you're are tracking multiple symptoms simultaneously.
  • Con: FAMs must be used consistently and adherently in order to work.
  • Con: It takes effort to track biomarkers like temperature, mucus, and cycle, even though apps and devices make this easier.
  • Con: You can’t always have vaginal sex when you want when using FAMs, unless you’re open to using another birth control option. If you choose to use another birth control method, your likelihood of becoming pregnant translates to the reported effectiveness of the alternate method.
  • Con: FAMs do not protect against STIs. **

Whether you choose to rely on FAMs as a form of contraception or not, it’s undeniably cool that our body naturally gives us clues into our cycle and fertility. (In other words, we hope you check out the sticky stuff in your underwear regardless.) We’re especially excited to see that the FAM space, which is ripe with high-tech technologies and devices, is more...well...fertile.

“Basal Body Temperature for Natural Family Planning.” The Mayo Clinic. 12 Jan. 2018, https://www.mayoclinic.org/tests-procedures/basal-body-temperature/about/pac-20393026. Accessed 06 March 2018.

“Cervical Mucus and Your Fertility.” American Pregnancy Association. http://americanpregnancy.org/getting-pregnant/cervical-mucus/. Accessed 06 March 2018.

“Fertility Awareness.” Planned Parenthood. https://www.plannedparenthood.org/learn/birth-control/fertility-awareness. Accessed 06 March 2018.

Frank-Herrmann, P. “The effectiveness of a fertility awareness based method to avoid pregnancy in relation to a couple's sexual behaviour during the fertile time: a prospective longitudinal study.” Human Reproduction. 22.5. (2007): 1310-9. NCBI. Web. 06 March 2018.

Girija, B. “Effect of different phases of menstrual cycle on physical working capacity in Indian population.” Indian Journal of Physiology and Pharmacology. 55.2. 165-9. NCBI. Web. 06 March 2018.

“How Ava Works.” Ava. https://www.avawomen.com/how-ava-works/. Accessed 06 March 2018.

Mohaned, S. “Pulse Rate Measurement During Sleep Using Wearable Sensors, and its Correlation with the Menstrual Cycle Phases, A Prospective Observational Study.” Scientific Reports. 7. (2017): 1294. Scientific Reports. Web. 06 March 2018.

Scherwitzl, E. “Perfect-use and Typical-use Pearl Index of A Contraceptive Mobile App.” Contraception. 96.6. (2017): 420-5. Elsevier. Web. 06 March 2018.

Thijssen, A. “Fertility Awareness-Based Methods’ and subfertility: a systema­tic review.” Facts Views Vis Obgyn. 6.3. (2014): 113–123. NCBI. Web. 06 March 2018.

“What’s the calendar method of FAMs?” Planned Parenthood. https://www.plannedparenthood.org/learn/birth-control/fertility-awareness/whats-calendar-method-fams. Accessed 06 March 2018.

“What’s the temperature method of FAMs?” Planned Parenthood. https://www.plannedparenthood.org/learn/birth-control/fertility-awareness/whats-temperature-method-fams. Accessed 06 March 2018.

Wilcox, A. “The timing of the ‘fertile window’ in the menstrual cycle: day specific estimates from a prospective study.” BMJ. 321.7271. (2000): 1259-62. NCBI. Web. 06 March 2018.

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English Taylor

English Taylor is a San Francisco-based writer and birth doula. Her work has been featured in The Atlantic, Healthline, LOLA, and THINX. Follow English’s work at https://medium.com/@englishtaylor.

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