The next generation of birth control pills may also help prevent cancer, protect against STDs, and even extend a woman's fertility.
By Denise Mann
Reviewed By Charlotte Grayson
From thin patches that release weekly doses of hormones to insertable contraceptive rings that release hormones for three weeks, the past three years have ushered in more advances in birth control than the past two decades.
Have we hit the limit of innovation? Not even close, experts tell WebMD. Gleaning their crystal balls, reproductive health experts tell WebMD that the future will likely herald forms of birth control that accomplish two jobs in one - just like certain low dose birth control pills are often prescribed to treat acne.
"So much is happening now," says Lawrence B. Finer, PhD, assistant director of research at the Alan Guttmacher Institute, a nonprofit research organization in New York City. And "the idea that a male pill or a female pill could be prescribed as non-contraceptive (medicine) is something that may start to play a more important role in contraceptive use."
For example, what if a male contraceptive also protected men from testicular and prostate cancer? And what if that same contraceptive also reduced chances of going bald?
Here's what's moving steadily and stealthfully down the contraceptive pike:
A Career Pill That Extends Fertility
Who says you can't have it all? Canadian researchers are studying the possibility of a "career pill." While it's at least 15 years from being on the market, such a pill may one day allow women to delay ovulation during their teens and 20s, resuming it when they are ready to have children. It also may delay the onset of menopause into the late 50s or 60s.
Women frequently have more difficulty becoming pregnant in their mid-30s as the number and quality of their eggs decline. This pill could slow down the biologic clock. By interrupting the body's signal to release an egg monthly, a woman could potentially preserve the use of eggs until later in life. What's more, it might also allow women to pursue careers without worrying about the increased fertility problems that may arise with advancing age. The research is being conducted at Royal Victoria Hospital in Montreal, Canada.
Male Hormone Shots That May Protect Against Cancer
It's not just a dream. Past attempts to create a birth control pill for men have been largely unsuccessful, but times are changing. New hormonal therapies for men are being studied that would not only prevent pregnancy, but some suggest they may also protect against prostate and testicular cancer, as well as benign enlargement of the prostate gland. They may even reduce acne and baldness!
"In U.S. and elsewhere, researchers are developing injectable hormonal contraceptive methods for men that would be given in the arm every two months," says Christina Wang, MD, a professor of medicine at the University of California at Los Angeles. "There are also studies to develop implants that last longer," she says.
In Europe and the U.S., researchers are looking at combinations of testosterone, (the primary male sex hormone) and progestin. "The two hormones, when given together, suppress production of sperm."
Wang tells WebMD that studies are well underway in China using testosterone alone as a monthly injection in 1,000 men. Here in the U.S., she says, "We are trying to identify the best combination of testosterone and progestin and that will take a few more years."
Already, "we know that they will work and suppress sperm counts to near zero. So, now we need to find the best combination using the lowest doses of testosterone available. And it needs to be delivered in user friendly method while maintaining efficacy," she tells WebMD.
Then, doses need to be tweaked to assure protection against pregnancy and the least amount of side effects. Testosterone alone suppresses sperm production, but it can cause bad side effects, including reducing high-density lipoprotein (HDL) or "good" cholesterol.
So when will we see such a method? "Maybe 10 years or less in the US," she says, "and in the Asian countries, maybe faster."
Will anyone take it? "From the studies that have been done, (researchers and pollsters) think that men will take it," Wang says. "There is a market for male contraception." Currently, men have no birth control method that is easily reversible besides the condom. Couples in a steady relationship often tire of condoms, but aren't yet ready for a vasectomy.
Chemical Barriers That Prevent Sexually Transmitted Diseases
In the future, creams applied topically to the vagina by women may provide dual protection against pregnancy and sexually transmitted diseases including HIV, the virus that causes AIDS.
They are called microbicides, says A. Robert Neurath, PhD, head of biochemical virology laboratory at the Lindsley F. Kimball Research Institute, the research arm of the New York Blood Center in New York City. "It's a broad term which covers compounds that kill viruses and or other STDs," he says.
Neurath's team is studying a compound known as cellulose acetate phthalate (CAP). And while it may not sound familiar, CAP has been used for 40 to 50 years as a coating on medications such as aspirin, he tells WebMD. It turns out that it's also an active compound against HIV and herpes, as well as against non-viral STDs. Neurath and colleagues came across CAP when they screened compounds already known and produced in large quantities, thus inexpensive.
"The idea is use it in a cream form or another form like film before sex to prevent STDs," he says. "Possibly this compound or another one in trials may also prevent pregnancy."
Ideally, such a compound would be useful in developing countries, Neurath says. Once much hope was pinned on the spermicide nonoxynol-9 (N-9), but recent studies have shown that does not reduce the risk of sexually transmitted infections. In fact, N-9 may irritate the vagina, vulva, penis, and rectum, and thus may actually increase susceptibility to STDs, including HIV.
CAP is set to start human trials in the next weeks or months.
"In the context of developing countries, microbicides can be used as a female-controlled method to prevent STDs," Finer says. Vaginal creams offer clear advantages over condoms. A woman wouldn't have to convince a man to use this method of protection; indeed, he wouldn't even be aware she was using it.
Emergency Birth Control Pills To Stop Conception After Sex
Emergency pills use higher doses of standard birth control hormones to prevent pregnancy after sex. They're already on the market, but you must have a doctor's prescription, which can be difficult or costly to get on a weekend or on short notice. Women's Capital Corporation has applied to the U.S. Food and Drug Administration to sell its emergency pill, Plan B, over the counter without a prescription. This way, if a condom breaks on a Friday night, women could have a stash of pills on hand to use when they're most effective, within 72 hours of intercourse.
Continuous Birth Control to Prevent Menstrual Periods
The first continuous birth control pill - which suppresses periods as well as pregnancy - is expected on the market in 2003. Finer at the Alan Guttmacher Institute predicts that many forms of continuous birth control will soon follow. Women may be able to wear a patch for 6 months, for example, to menstruate just twice a year. Or they may be able to insert a vaginal ring that lasts for a year. These products are not yet in clinical trials. But if consumer demand is there, Finer says, manufacturers will rush to it.
Vaccines Against Pregnancy
Finer adds that contraceptive vaccines, called immunocontraceptives, may also become available in the future. Such vaccines would affect fertility by regulating the body's immune response. In a nutshell, they would stimulate the immune system to shut down some of the functions necessary for a pregnancy. Such vaccines are under study here and abroad.
Published July 17, 2003.
SOURCES: Adelaide G. Nardone, MD, medical advisor for Vagisil Women' Health Center. Christina Wang, MD, professor of medicine at the University of California at Los Angeles. Lawrence B. Finer, PhD, assistant director of research at Alan Guttmacher Institute. A. Robert Neurath, PhD, head of biochemical virology laboratory at the Lindsley F. Kimball Research Institute.
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