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Not your grandmother

Not your grandmother's guide to fertility awareness methods

6 min read

“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 the Natural Cycles 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 like Natural Cycles, Kindara, Ava, Glow, Clue, Ovia Health, and Groove to just name a few. 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, from what they are to the technologies enabling successful use.

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. However, when FAMs are used in conjunction, this rate improves. For example, this study indicates that when the temperature and cervical mucus FAMs are used simultaneously, the pregnancy prevention rate is 99.6 percent when no unprotected intercourse occurs during fertile days.

Fortunately, 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, brands like Kindara, Natural Cycles, and Ava make multiple FAMs easier to access in one place and use more effectively by introducing technology, data, and algorithms.

Breaking down the tech

Ava: Temperature, calendar, and other methods

Ava is a bracelet that detects your fertile window—the six days when you can get pregnant during your cycle—while you’re sleeping. Overnight, the bracelet collects bio markers that are proven to be associated with fertility, like temperature, resting pulse rate, breathing rate, and more. In the morning, you sync this the bracelet with the app to get insight into your cycle. According to the website, Ava has been shown to detect an average of 5.3 fertile days per cycle at 89 percent accuracy.

Natural Cycles: Temperature and calendar methods

Natural Cycles provides you with a thermometer to measure your temperature each morning. Once this measurement is inputted into the app, you’re told whether it is a “red” or “green” day. Red days indicate your fertile window, while green days are those when it’s OK to have unprotected vaginal sex.

In December 2017, a clinical study of over 20,000 Natural Cycles users concluded that, “Natural Cycles’ perfect use [pregnancy prevention] efficacy is 99 percent. This refers to the efficacy rate of using Natural Cycles during one year in which a pregnancy may occur despite having no unprotected intercourse on red days. Natural Cycles’ typical use efficacy is 93 percent. The typical use efficacy refers to the efficacy rate of using Natural Cycles during one year in which pregnancy may occur due to any possible reason; from the app falsely attributing a green day (method failure) to having sex on a red day without protection (human error). ”

Kindara: Temperature, cervical mucus, and calendar methods

The Kindara app asks users to input their daily temperature, cervical secretions, and when they begin their period. This data creates fertility charts for users, allowing them to see whether they are fertile or not. Like Natural Cycles, Kindara also provides users with an oral thermometer.

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 are said to be up to 99.6 percent effective at preventing pregnancy.
  • Con: FAMs must be used consistently and adherently in order to achieve this high efficacy.
  • Con: It takes effort to track biomarkers like temperature, mucus, and cycle, even though apps and devices like Natural Cycles, Ava, and Kindara 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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