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July 28, 2000 -- Someday women may be able to take a birth control pill for years on end -- stopping only when they want to become pregnant or go through menopause. By doing this, woman may be able to safeguard their eggs from the natural cycle of death and, in theory, save them until they want to use them to get pregnant.
At least that's the goal of a new birth control medication now under development in Canada. The pill has been dubbed the 'career' pill because it would most likely be popular among women who want to delay having families in favor of careers.
Birth control pills available today prevent pregnancy by suppressing the monthly release of a mature egg, which occurs prior to menstruation. But even in women who take these pills, many immature eggs die each month. A woman's ovaries don't produce new eggs. Instead, they contain the full amount of eggs they will ever have before a woman is even born, and when all eggs are gone, menopause begins.
What Roger Gosden, PhD, and other fertility experts, hope to develop is a pill or other method that could halt the process of egg death -- effectively shutting down the 'biological clock' that regulates fertility and menopause. Because the quality and number of eggs decline over time, such a product could help women in their 30s or 40s who have trouble conceiving. Gosden is director of reproductive biology at McGill University Health Center in Montreal.
A spokeswoman for Gosden tells WebMD the research is at a preliminary stage and such a product is 10 to 15 years away from possibly going on the market. Gosden's goal, says the spokeswoman, is to allow women to devote time to a career, if that is what they want, and to postpone child-bearing until they are ready, regardless of whether their body has aged past the child-bearing prime time.
Among the many issues to be worked out, admits Gosden, is whether the eggs would be capable of being fertilized or would be damaged. "For example, if a woman starts to take this new pill at the age of 17, and only stops at 47 years old, will her eggs have the characteristics of a woman of 47 or a woman of 17? We don't know, and we won't know until the research is complete," Gosden said in an interview with a Montreal publication.
Such a pill or device would also have an additional effect beyond preserving fertility. If ovulation is suppressed, the woman would also be suppressing monthly menstruation. Women can suppress their periods by taking a birth control pill continuously for weeks on end, without the so-called skip week, in which they stop or take an inactive pill for seven days. This is usually only done for 'special' occasions, such as honeymoons or vacations.
Another pill now being tested by women around the country, called Seasonale, would also suppress ovulation. It would be taken for three months at a time, with one week off in between, and would cause women to have only four periods a year. If approved by the FDA, Seasonale should be on the drugstore shelves in two or three years.
Some fertility experts tell WebMD Gosden's goal is shared by many and is not likely to be easily achieved. "On a theoretic basis, this is what a lot of people have been interested in trying to do. This is something that everybody has thought about," says Rogerio Lobo, MD, chairman of the department of obstetrics and gynecology at Columbia University and Presbyterian Medical Center in New York.
Kirtly Parker Jones, MD, an associate professor of reproductive endocrinology at the University of Utah School of Medicine, calls it "an interesting idea without a shred of scientific evidence."
"The fundamental scientific questions about why [eggs die] is yet unknown -- so until we firmly understand that fundamental question, we cannot devise a medication to stop it -- and birth control pills as we currently know them certainly won't," Jones says.
She adds that women should think twice about delaying childbirth. "Polls have shown that women who had their kids before they started their careers are much happier than women who try to fit their kids in the middle or struggle to have kids near the end," she tells WebMD.
However, James Simon, MD, who is one of the physicians studying Seasonale, tells WebMD he would welcome such a development, provided the medication is safe and is able to maintain normal hormone levels.
"I don't know what the compound would be. Once the information is clearer we would have a better idea of whether the drug has long term side effects," says Simon, a clinical professor of medicine at George Washington University School of Medicine and medical director of the Women's Health Research Center in Laurel, Md.
Simon adds that there are benefits to long-term birth control use, which he has occasionally prescribed to help patients with chronic pelvic pain, PMS, and endometriosis, a painful condition in which tissue from the lining of the uterus migrates to other parts of the body.
"In 25 years of practice I have had women on extended doses of contraceptives," he says. "I have a couple [of patients] who have been on oral contraceptives for six to eight years, and they don't want to become pregnant, so we aren't taking them off."