4 Common Myths About FABMs

A Guest Post by Chavah Hull

Who’s had this conversation before:

You: “I want to avoid getting pregnant right now, but I’m not happy with the pill.”

Doctor: “I understand. Let’s switch you to this type instead.”

You: “Um…no, I don’t want hormonal birth control at all.”

Doctor: “Oh, I see. You want an IUD?”

You: “Actually, I started using fertility awareness, and it’s…”

Doctor: [Interupting you while shacking their head] “I’ll see you in a month or two to confirm pregnancy.”

I practice an evidence-based fertility awareness method, NOT the rhythm method. However, many people, even doctors, still think fertility awareness is a glorified name for the rhythm method. In this article, we will examine 4 Common Myths regarding FABMs and learn the truth behind the misconceptions surrounding natural birth control. 

MYTH 1: FABMs are the rhythm method

Rhythm Method 101: Definition & History

Roughly 100 years ago, in the 1920s, two scientists in different parts of the world discovered a connection between ovulation and menses. Dr. Ogino (in Japan) and Dr. Knaus (in Austria) found that ovulation, on average, occurs anywhere from 12 to 16 days BEFORE a woman’s next period starts. This discovery was exciting news, and the findings began spreading quickly within the medical world.

In 1932, a scientist, Dr. Leo J. Latz, living in Chicago, brought this idea to the general populous in America. The term “Rhythm Method” seems to have originated from Dr. Latz’s published book, The Rhythm of Sterility and Fertility in Women. In this publication, Latz, utilizing the discoveries of Ogino and Knaus, presented a “fairly predictable” calculation that a woman could use to achieve or prevent pregnancy. If a woman were looking to avoid pregnancy, she would not have intercourse between days 12 to 16 in her monthly cycle (assuming she had a 28-day cycle). 

The book quickly gained popularity and had sold over 200,000 copies by 1942. Along with Dr. Latz’s book, a new “device” came on the market, The “Rythmeter.” The Rythmeter was a hand-held calculator that women and doctors could use to estimate fertile and infertile periods of the menstrual cycle. However, even the inventor of this new device warned women not to use it without having a record of at least nine months of past menstrual cycles. Man, oh, man, now that’s commitment!

[Image used from https://case.edu/affil/skuyhistcontraception/online-2012/Rhythm-method.html]

FACT Behind Myth 1

The rhythm method is no longer considered an evidence-based fertility awareness method (FABM). Present-day FABMs are based on your body’s biomarkers, such as bleeding, mucus, temperature, and hormonal indicators in the urine. These methods are backed by sound research and adaptable to each woman and each individual cycle.

These days, the evidence-based FABMs recognize that calculating the time of ovulation can be tricky. There is no one-size-fits-all calculation. Ovulation varies from woman to woman, and a woman can ovulate at a different time each month. Stress, illness, or interruptions in the normal routine can also alter a woman’s cycle.

MYTH 2: FABMs aren’t effective in preventing pregnancy.

Effectiveness rates for avoiding pregnancy can be very high—over 98 percent in some studies. However, keep in mind that your effectiveness will be highest only if you follow all the instructions of your method and, ideally, if you work with an instructor. 

There are three main types (or categories) of FABMS:

1) Cervical Fluid/Mucus-only Methods 

Included in this category are the Billings Ovulation Method and the Creighton Model FertilityCare System. These methods rely heavily on cervical mucus (plus other discharges) throughout the entire cycle to determine fertile and non-fertile days. 

2) Sympto-Thermal Methods

Included in this category are NeoFertility, SymptoPro, TCOYF, Couple to Couple League, and others. Sypmto-Thermal methods rely on both cervical mucus (some encourage increased attention to cervical mucus such as NeoFertility) and temperature shifts in the cycle to determine fertility. 

3) Sympto-Hormonal Methods 

Included in this category are Marquette, FEMM, and Boston Cross Check. These methods may incorporate both cervical mucus and temperature, but they rely on testing hormones in the cycle, such as utilizing the Clearblue Fertility Monitor or LH strips.

Learn how to chart your cycles and use FAM to avoid pregnancy at HER Fertility School.

MYTH 3: You can’t use a FABM if you have irregular cycles

People who make this claim are still thinking of the rhythm method. FABMs are all about reading your body’s fertility signals directly (by measuring urine metabolites of hormones) or indirectly (by observing symptoms like cervical mucus and BBT). Additional cross-checks to fertility may include the wet or dry sensation while walking and your cervix’s position throughout your cycle. 

When cycle length changes, chart observations change, and the fertility window then also shifts. A certified instructor will be able to help you navigate your cycle. Women experiencing abnormal cycles due to PCOS, endometriosis, continual mucus, or postpartum may need additional support from their instructor.

MYTH 4: FABMs are expensive to learn and use

Prices do vary, but they aren’t all expensive. Many of the price points may depend on if the instruction is being held online or in-person. Prices also vary due to the instructor’s training and experience working with clients. You also can find membership models, group coaching, or one-on-one coaching. There is an option available for everyone. FABMs are not a one-size-fits-all just like our cycles are not one-size-fits-all.

I am happy to answer any questions you may have about charting your cycle. Feel free to schedule a complimentary 20-minute Discovery Call to determine the best method to meet your needs and lifestyle. I can be reached at chavah@virtusfertilitycare.com.

About the Author

Hi, I’m Chavah Brooke Hull, FCP. I’ve taken everything I’ve learned from my past 10 years of working with women and families along with 8 years of my own personal charting experience and channeled into my work as a Chart Your Cycle Fertility Coaching. I am a fertility awareness coach, childbirth educator, doula, and postpartum advocate. I help women avoid the pill and become confident in charting their cycles.

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  1. Museum of Applied Arts and Sciences, NSW Government, accessed 25 June 2020, https://collection.maas.museum/object/345735
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