There's a simple, free step women can take to help them get pregnant, yet few women know about it, a new study shows.
Women who use the technique, known as cervical mucus monitoring, were more than twice as likely to conceive than women who did not track their cervical mucus.
"This technique can be used to help people get pregnant faster," said Dr. Anne Steiner, an ob-gyn at the University of North Carolina at Chapel Hill and senior author of the paper. "It's exciting to potentially say this is a real way to help people; it's so cheap and easy."
Cervical mucus changes in viscosity throughout a woman's cycle. When an egg develops in the ovary, estrogen is released, making the mucus thinner and slippery. This enables sperm to swim to the egg more easily. After the egg is released, a spike in progesterone causes mucus to thicken and act as a barrier to other sperm. Thus, tracking the state of this cervical mucus gives insight into a woman's fertility.
The study followed 331 women ages 30 to 45 with no known fertility problems who had been trying to conceive for three months or less. Women were asked to categorize their cervical discharge as one of four types: type 1, dry or nonexistent; type 2, damp; type 3, thick and white or yellowish; and type 4, transparent and slippery.
Previous studies had found that women having intercourse on days when they had type 4 mucus were at least two to three times more likely to get pregnant than if they had intercourse on days when they had type 1 or type 2 mucus.
In the new study, the women who checked their cervical mucus consistently were 2.3 times more likely to get pregnant over a six-month period. [5 Myths About Fertility Treatments]
However, the researchers also found that very few women were actually diligent about monitoring it daily — only 6 percent did it consistently, whereas 54 percent of the women didn't bother to check their cervical mucus at all.
These women might be cheating themselves out of an effective and simple method of tracking their fertility, the researchers said. For example, simply counting the days between menses on the calendar can prove inexact, even for women with very regular cycles, and ovulation predictor kits, which track urinary levels of luteinizing hormone, can be expensive, costing between $20 and $40 per month.
Tracking body temperature to indicate ovulation also has limited usefulness because the signature temperature spike occurs after a woman has ovulated, giving retrospective information that only comes in handy for the next cycle, the researchers said.
Dr. Wendy Vitek, an ob-gyn at the University of Rochester Medical Center in New York, agreed that wider use of cervical mucus monitoring holds promise as a way to increase the odds of pregnancy.
"It makes intuitive sense that the women monitoring their cervical mucus more frequently had a better sense of when they're ovulating...You do need to make involved observations to know when you're at peak fertility," said Vitek, who was not involved in the study.
However, the technique may not be right for everyone.
"A lot of women may not see their cervical mucus externally," said Dr. Elizabeth Ginsburg, an ob-gyn at Brigham and Women's Hospital in Boston.
"My concern is, you tell a patient to look for this type of discharge, and [if] she doesn't see it, she may worry that she has fertility problems, when she's probably ovulating just fine," Ginsburg said.
The researchers suggest that women who are trying to conceive and who are able to observe their cervical mucus easily keep a daily record of the vaginal discharge, noting which category it falls into (1 through 4). On the days when they note type 4 discharge, it's probably the best time for women to try to conceive.
The study was published online July 12 in the journal Fertility and Sterility.