[Today’s guest post by JoAnna Wahlund is part of our paid blogging program.]
Judging by the comments after last week’s post regarding pro-lifers and contraception, there seems to be a great deal of misunderstanding regarding Natural Family Planning (NFP). Since July 20-26 is NFP Awareness Week, I decided to provide this basic overview of NFP to clear up any misconceptions (no pun intended!) and provide additional information for those who are interested in learning more about it.
What is Natural Family Planning?
NFP is a method of avoiding or achieving pregnancy (it can serve either purpose depending on the intent of the users) by identifying the biological markers that indicate natural fertility or infertility (basal body temperature, cervical mucous, presence of certain hormones in urine) so that users can either avoid or engage in sexual intercourse, depending on their intention. It can also be used to monitor gynecological health and identify possible problems. NFP is “natural” in that it does not utilize synthetic hormones or substances, barriers, or invasive devices.
Isn’t NFP also called “the rhythm method”?
No, although this is a common misconception. The rhythm method (also called “the calendar method”) is essentially the most basic type of NFP, but it is also the least effective. The rhythm does not take into account a woman’s biological markers that indicate levels of fertility. Instead, it is entirely dependent upon the assumption that every woman has a clockwork 28-day cycle, with menstruation occurring on day 1 and ovulation occurring on day 14. That’s only true for roughly 30% of women, and many outside factors – diet, nutrition, stress, illness – can affect the length of each cycle even for women who do have regular cycles.
I’ve often heard other women say that they can’t use NFP because they have irregular cycles, and unfortunately that’s a common myth which hearkens back to the misconception of NFP = rhythm method. Many women are told by their OB/GYNs that they have “irregular” cycles when they simply have a longer cycle length – say, 35 days instead of 28. (I once had a 75-day cycle. Thankfully, that wasn’t typical!) NFP works with any and all cycle lengths.
What are the types of NFP?
They include, but are not limited to, Billings, Creighton, Sympto-Thermal, and Marquette, as well as the Fertility Awareness Method (FAM). For brevity’s sake I’ll only discuss these, but there are many additional forms that are offshoots of these methods.
Billings Ovulation Method: The Billings Ovulation Method of NFP (BOM) is named after Drs. John and Evelyn Billings, but was developed by many different medical professionals based on extensive research which began in 1953 (you can read a comprehensive history of its development here). Its focus is on detecting fertile periods by charting the quantity, quality, and consistency of cervical mucous was well as the sensation at the vulva.
Creighton Model FertilityCare™ System (CrMS) is a modification of the Billings method and was developed in the late 1970s by Dr. Thomas Hilgers. It is the basis for NaPro Technology, which specializes in treatment of infertility and menstrual cycle disorders. Like Billings, it tracks the biological marker of cervical mucous.
The Sympto-Thermal Method (STM) builds off of the mucous observations of the Billings and Creighton methods and adds another biomarker: basal body temperature (BBT), which is the body’s temperature each morning immediately after waking but prior to rising. (The temperature will be low in the first part of a woman’s cycle but spike once ovulation has occurred.) The correlation of BBT to a woman’s menstrual cycle was discovered by German priest Fr. Wilhelm Hillebrand in the 1930s. STM was not widely taught in the United States until John and Sheila Kippley, in partnership with Dr. Konald Prem, a professor at the University of Minnesota Medical School, founded the Couple to Couple League International (CCLI) in 1971.
The Fertility Awareness Method (FAM) is essentially a secularized approach to the Sympto-Thermal Method. For decades, nearly all NFP promotion was done by the Catholic Church and related entities. Toni Weschler changed that in 1995 with the publication of her book “Taking Charge of Your Fertility.” The main difference between FAM and other NFP methods is the (optional) addition of using condoms during the fertile period to prevent pregnancy, as opposed to abstinence.
What do you call people who practice NFP? Parents!
HAHAHAHAHA! I’ve only heard that one half a million times.
In all seriousness, the effectiveness of NFP for avoiding pregnancy is comparable to contraceptive methods such as the birth control pill:
- An extensive sampling of effectiveness for the Creighton method yielded a perfect use success rate of 99.5% and a user failure rate of 3.2%.
- The Billings Method has been taught in China, Indonesia, and India, and studies there resulted in a perfect use rate of 99%, with a user failure rate of around 5%.
- A 2007 study of STM/FAM in Germany found that the perfect use success rate was 99.6% – comparable to that of the birth control pill. The user failure rate was 1.8%, compared to the Pill’s user failure rate of 9%.
- A 2004 study published in the journal Contraception (as summarized on the Marquette University NFP site, here) found a higher user failure rate for fertility awareness methods, an average of 10%, but again perfect use rates were 98-99%.
The CDC cites a user failure rate for “natural family planning or fertility awareness” methods as 24%, but they don’t cite any statistics for how that number was reached. I suspect that that number more accurately reflects the user failure rate for the rhythm method, which is around 25%.