Director’s Note: Dr. Elizabeth Osburn learned about the Billings Ovulation Method during the FACTS elective. She had assumed the method’s requirements, including consistent reporting of cervical mucus quality, would render it inaccessible to populations unable to read or write. Yet, this field trial conducted in India challenged her assumption. In her summary of groundbreaking research [1] by Bhargava et al published in 1996 in Contraception, she expressed her surprise at the successful outcomes reported. We hope this study will encourage you — as it inspired Dr. Osburn — to consider the relevance of fertility awareness-based methods (FABMs) even in populations with low literacy rates.

Introduction

This is a brief synopsis of the 1996 research article by Bhargava et al titled, “Field Trial of Billings Ovulation Method of Natural Family Planning.” [1] Through this trial, the Billings Ovulation Method was explored as an alternative to existing methods of family planning in India, where they experienced a high rate of dissatisfaction with hormonal birth control. Around 20-60% of users discontinued intrauterine devices (IUDs) or oral contraceptive pills (OCPs) after 1 year, and 15% had unmet family planning needs.

“Through this trial, the Billings Ovulation Method was explored as an alternative to existing methods of family planning in India, where they experienced a high rate of dissatisfaction with hormonal birth control.”

This natural or fertility awareness-based method (FABM) is based on a woman’s perception of her cervical mucus. Cervical mucus production depends on the hormones released during the different phases of the menstrual cycle. When a woman is fertile, estrogen is the dominant hormone and produces cervical mucus that is thinner and feels more slippery. On infertile days, mucus is thicker and may be perceived as dryness. This is known as the basic infertile pattern.

When the goal is to avoid pregnancy, the Billings Ovulation Method establishes rules to guide which days to have intercourse. The first early day rule states that couples should not have intercourse on days of heavy bleeding because this may obscure a patient’s perception of cervical mucus. They may have intercourse on infertile days but should alternate days of intercourse during this time, since seminal fluid may affect cervical mucus observations. Couples should also avoid intercourse on any day in which the basic infertile pattern is broken by mucus or bleeding, and wait 3 days after the interruption before attempting intercourse.

“The first early day rule states that couples should not have intercourse on days of heavy bleeding because this may obscure a patient’s perception of cervical mucus.”

The goal of this trial was to study the effectiveness of the Billings Ovulation Method to avoid pregnancy with a larger and more diverse patient population than previous studies. This could in turn influence the health and family welfare policy to include the Billings Ovulation Method as a teachable and efficacious method of natural family planning.

Methodology

The trial was conducted in 1987 and included 2,059 volunteers aged 15-35 with regular menstrual cycles lasting 26-31 days. The participants were from 5 different states in India and represented all socioeconomic classes, both rural and urban. They received education on the menstrual cycle, changes in cervical mucus, and the rules of the Billings Ovulation Method. They were given charts to record their cervical mucus, with accommodations (symbols/colors) for individuals with lower literacy. The women were instructed to abstain from sexual intercourse completely during the first cycle to establish a basic infertile pattern, and to also abstain on fertile days thereafter. They were followed for 21 months with regular check-ins to review their charts and ensure understanding of the method. 

Results

Of the volunteers who accepted this method, 32% were considered non-literate, and 7% had minimal literacy. Most of the patients were aware that family planning options existed but had never used them. Continuation rates were high at 6 months (88%) and 12 months (76%), then dropped off at 18 months (62%) and 21 months (52%). These discontinuation rates were more severe among the rural participants. Method failure was as low as 1.5, and use failure was 15.9, per 100 users at 21 months. Failure rates were also higher among rural participants and women less than 25 years of age. 

Discussion

The Billings Ovulation Method proved to be useful to the India Family Planning Program with its low use failure rate and higher continuation rate than other birth control options. This study showed that fertility awareness-based methods can be very effective, even in populations with low literacy.

“The Billings Ovulation Method proved to be useful to the India Family Planning Program with its low use failure rate and higher continuation rate than other birth control options.”

Before reading this article, I assumed a method that requires regular recording of cervical mucus quality would be quite inaccessible to people who cannot read or write, but I was mistaken. With proper training and accommodation, the Billings Ovulation Method can be a useful tool for any patient desiring natural family planning. Most participants in this study were housewives, which reflected the population of India at the time, but this may weaken the study’s relatability to the modern world.

It would be valuable to see data on the Billings Ovulation Method for working and unmarried women, as well as its efficacy and continuation rates compared to data on newer hormonal options with better side effect profiles. Still, this article is relevant to women’s health for preventing and achieving pregnancy and I plan to use it in my future practice.