TUESDAY, June 25, 2002 (HealthDayNews) -- For couples who want to use natural family planning, a new method of birth control developed by Georgetown University researchers may be the answer.
Some religions forbid the use of artificial means of birth control, leaving their followers with few options to prevent unwanted pregnancies.
One natural family planning option that's available is the rhythm method, but according to Georgetown University researcher Victoria Jennings, people don't often follow this method properly because it's complicated to calculate the exact days you must abstain from sexual intercourse.
That's why Jennings and her colleagues at Georgetown's Institute for Reproductive Health developed a new method of natural family planning, called the Standard Days Method. To help women keep track of which days are safe and not safe for sex, the researchers also developed a visual reminder, called CycleBeads.
This new method had a 95 percent success rate in preventing pregnancy during a 13-month study, the researchers report in the current issue of the journal Contraception.
"[The Standard Days Method] is natural and effective," Jennings says. But, "it's not for everybody."
This new method of birth control is best for women who have a 26- to 32-day menstrual cycle, who are in a committed relationship, and who are not at risk for sexually transmitted diseases, she says.
To develop the Standard Days Method, Jennings and her team analyzed data from the World Health Organization on 7,500 menstrual cycles. Using a computer model, they identified the 12-day window when a woman is likely to be fertile. On these days, women must abstain from sexual intercourse if they don't wish to become pregnant. This 12-day period takes into account the 24-hour lifespan of a woman's egg and the potential five-day lifespan of a man's sperm.
Next, they wanted to come up with a simple way for women to keep track of where they are in their cycle. CycleBeads is the result. It's a string of 32 color-coded beads with a movable rubber ring. Each day, a woman moves the ring to the next bead. When the ring is on any of the brown beads, pregnancy is very unlikely.
To test the efficacy of the Standard Days Method and CycleBeads, the researchers recruited almost 500 women in Bolivia, Peru and the Philippines. The women were between 18 and 39 years old and had regular menstrual periods. They also had to be willing to abstain from sexual intercourse for 12 days every cycle during the 13-month study.
Forty-three women got pregnant during the study, but 65 percent of those women admitted to having unprotected sex during their 'fertile' time.
That means that during typical use, 12 percent of women using the Standard Days Method will become pregnant. If used properly, however, only 5 percent would become pregnant. Comparatively, male condoms have a 14 percent pregnancy rate with typical use, but only a 3 percent pregnancy rate with correct use. With the rhythm method, typical use would result in a 25 percent pregnancy rate while perfect use would result in a 10 percent pregnancy rate. Less than 1 percent of women using birth control pills get pregnant during a year of use.
"This is not a foolproof method of birth control, and it doesn't provide a barrier against sexually transmitted diseases," says Dr. Sanjay Agarwal, acting director of reproductive medicine at Cedars-Sinai Medical Center in Los Angeles. "A 12 percent rate of pregnancy may be unacceptably high for some people."
However, he says, it may be a good option for people with religious concerns, though he thinks the period of abstinence may be unnecessarily long for women with very regular menstrual periods who could more accurately figure out when their fertile times are.
What To Do
To learn more about the Standard Days Method and CycleBeads, visit the Institute for Reproductive Health.
For more information on the rhythm method, go to the Nemours Foundation.
