More Options For Women Seeking Emergency Contraception
Tiny dose of abortion drug works as well as standard
FRIDAY, Dec. 6, 2002 (HealthDayNews) -- Women may now have more options when it comes to emergency contraception.
One is simply an easier method of taking an already-used medication here in the United States, while another is a much smaller dose of the drug called RU486, commonly used to abort pregnancies.
In a new study, World Health Organization (WHO) researchers compared the safety and efficacy of levonorgestrel taken in two doses (already used here and typically called Plan B) to the same drug taken in a single dose of double strength, and to one 10-milligram dose of mifepristone.
The researchers, led by Dr. Helena von Hertzen of the department of reproductive health and research at the WHO, found the three different combinations of drugs to be equally effective and they result in few adverse side effects for women who take them within 72 hours of unprotected intercourse.
In the study, appearing in tomorrow's issue of The Lancet, there was an average 1.6 percent pregnancy rate among all groups. (This varies according to the time of month the woman had intercourse and when she sought emergency contraception, von Hertzen notes. Emergency contraception is generally considered 80 percent effective at preventing pregnancy).
The researchers conducted a randomized trial of 4,071 women who sought emergency contraception (EC) at 15 family planning clinics in 10 countries.
The women either received a single dose of 10 milligrams of mifepristone, a single dose of 1.5 milligrams of levonorgestrel, or two doses of 0.75 milligrams of levonorgestrel, given 12 hours apart.
"Some people may have anticipated that mifepristone would be somewhat more effective than the two levonorgestrel regimens," but this did not turn out to be the case, says von Hertzen.
Others may have expected to see differences in side effects, such as nausea or breast tenderness, but the drugs were fairly similar in their side effect profiles, she adds.
There were a few differences between the drugs. Most women menstruated within two days of the expected date, although women who received mifepristone tended to menstruate later than women who received levonorgestrel. This may not sound like a big deal, but to some women in can be, von Hertzen says. "If menses are late, even if the reason is delayed ovulation, women are worried about the situation. Earlier menstruation also makes it possible to start effective contraception sooner."
Those who received mifepristone had less bleeding due to the medication within the first seven days following treatment (31 percent in the levonorgestrel group versus 19 percent of those on mifepristone).
This can also bother some women, says Dr. Paul Blumenthal, an advisor to the Planned Parenthood Federation of America and a professor of gynecology and obstetrics at John Hopkins University. "Bleeding at unexpected times is worrisome," he says.
He says this study bears good news, because the more options a woman has, the better. Some women won't mind if their period is late and others will be very upset, just as some women will be more disturbed by unanticipated bleeding. "That's why there have to be these choices," he says. "It's really what the woman is most comfortable with."
Women in the United States have three choices right now when it comes to emergency contraception: Preven (a combination of levonorgestrel 0.25 milligrams and Ethinyl Estradiol 0.05 milligrams), Plan B, or the intrauterine device (IUD) inserted after unprotected sex, Blumenthal says.
This study suggests that women can now be offered an alternative to Plan B, he adds. "You could, based on the evidence, advise patients to take two pills of levonorgestrel at one time." This may mean more women will be protected from unwanted pregnancies, he explains. "Any time you ask a patient to do something less often with few side effects, compliance increases."
As for mifepristone, von Hertzen says it's not yet available anywhere: "Ten-milligram mifepristone is not registered, and hence on the market, in any country." Mifepristone, also known as RU486, was approved for abortion purposes in the United States, but a woman must take 600 milligrams.
Blumenthal suggests that if enough women ask for this form of emergency contraception, it may become available.
Von Hertzen advises women to note that while there may be more options of emergency contraception available, taking medication after unprotected sex should not become a regular form of birth control. "Long-term contraception or proper use of condoms is more effective and some methods can prevent up to 100 percent of pregnancies," she says. "It [emergency contraception] should be kept for emergency only, and should never replace other contraceptive methods."
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