Safer and more advanced contraceptives hit the market
Date: Monday, July 10, 2006
Source: Los Angeles Times (US)
Author: Shari Roan
Now, a birth control bonanza; As safer and more advanced contraceptives hit the market, women can tailor their methods to fit their lifestyles.
This is turning out to be a pivotal year in birth control.
In the last six months, the Food and Drug Administration has approved an oral contraceptive that eliminates a monthly menstrual period, and can prevent mood swings and other side effects. It also has approved two others that feature shorter periods. And soon it's expected to sign off on a yearlong oral contraceptive and a simpler version of a contraceptive implant.
Of course, there's no long-term data on the new methods -- and they aren't for everyone -- but doctors consider this new generation of birth control to be less risky and more sophisticated than the decades-old predecessors. And still in development are even safer, more advanced options -- with natural hormones and smoother delivery methods.
"Anytime there is a new method, there will be some women who say, 'Oh, thank goodness, there is something for me,' " says Dr. Carolyn L. Westhoff, medical director of the family planning clinics at N! ew York Presbyterian/Columbia University Medical Center in New York. "It's not that different than trying to find the best pair of jeans to fit your body."
That's not an easy thing to do. But what seems to fit many women is curtailing or eliminating menstruation altogether.
Two brands of birth control pills, both approved earlier this year and now available, feature shorter periods than the usual five to seven days. The products -- Loestrin 24 Fe and Yaz -- provide 24 days of active pills, forms of the hormones estrogen and progestin, followed by four days of placebo pills.
And in May, the FDA approved Seasonique, a slightly different version of Seasonale, which was approved in 2003 as the first continuous-use oral contraceptive. With Seasonale, which will become available in September, women take the active pills for 84 days followed by seven days of inactive pills to allow for a period. Seasonique, however, substitutes low-dose estrogen in place of the placeb! o pills so that a woman's hormone levels don't crash during the off we ek.
Finally, the FDA is considering an application to approve the first year-long oral contraceptive. Lybrel contains only active pills without any break for a period. "For the last 40 years of the pill, one thing we've done is we've lowered the dose for improved safety," Westhoff says. "But all along we were sticking to this original recipe of 21 days of hormones and seven days of placebo."
The shift to continuous-use oral contraceptives acknowledges a little known fact: Women don't need to have periods.
Although early pills were associated with high levels of hormones and a related risk of blood clots, the level of hormones in birth control pills has dropped dramatically in the last two decades. Now, even taking an active pill 365 days a year is not thought to be harmful, says Dr. David Portman, director of the Columbus Center for Women's Health Research in Columbus, Ohio.
Nor does the extended-use regimen appear to interfere with fertility. In a study of 1! 87 women presented in May at a meeting of the American College of Obstetricians and Gynecologists, researchers reported that almost 99% of the women had a period or became pregnant within 90 days of stopping the medication.
"There is no lingering effect of the medication in the body because it is metabolized very quickly," says Dr. Anne R. Davis, an assistant professor at Columbia University and lead investigator of the study. When oral contraceptives were first introduced decades ago, the placebo week "was put in there to mimic the natural cycle," she says. "It was done with the idea that the pill would be more acceptable to women. It wasn't done because of safety or effectiveness."
That's not to say the pills are right for everyone. For those with a shaky memory, the downside of a year-round pill is remembering it every day. In addition, women who miss pills may have more trouble determining if they are pregnant without a break from the pill for menstruation.
! "You would have to go on other symptoms to know if you're pregnant," D avis says. Oral contraceptive use during early pregnancy is not thought to be linked to birth defects, she says.
However, the effects of taking Lybrel during several months of pregnancy have not been specifically studied. And some health experts caution that there is a lack of data on continuous-use birth control pill regimens.
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Long-term protection
For women who find daily methods difficult, the first contraceptive implant to emerge since Norplant was removed from the market in 2002 is expected to be approved by the FDA later this year.
That earlier implant consisted of six matchstick-size rods that were placed under the skin of the forearm to release fertility-controlling hormones. But the product was plagued with problems, including the difficulty of inserting and removing the rods.
The new implant, Implanon, consists of a single rod that can prevent pregnancy for three years and is now under FDA review.
Other long-term contraceptives approved! in recent years include NuvaRing, which became available in 2001. A small, flexible vaginal ring that releases hormones, it's worn for three weeks then removed for one week. And Mirena, a hormone-releasing intrauterine device, was approved in 2001 and provides five years of protection.
Another long-term contraceptive, the injectable Depo-Provera, was reformulated in 2004 with lower doses of hormones. The newer formulation is injected four times a year under the skin instead of into the muscle, Westhoff says. A weekly method has also found a niche. Ortho Evra, the first transdermal contraceptive patch, was approved in 2001. Each hormone-releasing patch is worn for one week; after three weeks, no patch is worn to allow for a menstrual cycle.
Some of the newer products do carry some specific risks. In November, the FDA changed the labeling for the Ortho Evra patch to warn that the product exposes women to higher levels of estrogen than most birth control pills, which ! may increase the risk of blood clots. And Depo-Provera has been found to reduce bone density, although the newer formulation is thought to cause less bone loss.
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Enhancing methods
Simply having more options isn't enough for scientists, doctors -- or patients.
Researchers are working to refine existing contraceptives and create new ones. Although hormonal methods are now considered extremely safe, they do carry some risks. Women with a history of blood clots, heart attack, stroke, liver disease or cancer of the breast or sex organs are generally not advised to use hormonal contraceptives.
So as scientists continue to study how to reduce the risks of birth control, they're exploring the use of the natural hormone estradiol to replace ethinyl estradiol, the synthetic version of estradiol found in the majority of hormonal contraceptives that can increase the risk of blood clots and cardiovascular events in susceptible women.
The Population Council, a nonprofit organization that conducts health research, is studying a hormo! nal contraceptive that uses natural estradiol combined with nesterone, a synthetic progestin that closely resembles the natural hormone progesterone. Although nesterone can't be absorbed orally, the combination could be used in a spray or gel applied to the skin.
"The combination will be much more natural than all of these synthetic combinations that are available at the moment," says Regine Sitruk-Ware, executive director of research and development. "We could expect to avoid the metabolic and cardiovascular side effects."
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