Male Contraception: Progress Slow but Steady
Saturday, April 12, 2008; 12:00 AM
SATURDAY, April 12 (HealthDay News) -- For now, men who want to do their part for birth control have meager choices: A vasectomy -- meant to be permanent -- and condoms.
For years, experts have predicted that male contraception is under development and that more choices will be here soon.
But when? Experts agree it's still a ways off, but it's getting closer.
"It has been slow," said Dr. Ronald Swerdloff, a researcher in the quest to find feasible male contraceptive methods. But there are good reasons for that slow pace, added Swerdloff, an endocrinologist and chief of the division of endocrinology at Harbor-UCLA and professor of medicine at the Harbor-UCLA Medical Center in Los Angeles.
Pharmaceutical companies are reluctant to take on a new product quickly because of untested liability issues, he said. And "one of the biggest single issues has to do with the fact that contraception in general is a difficult area it would be used by large numbers of healthy individuals." The safety threshold, he noted, is high. Still, he added, more options are moving closer.
"If we really focus on studies, with funding, it could be four or five years" before more options might be available, said Elaine Lissner, director of the Male Contraception Information Project, a San Francisco-based organization.
The problem, she added, is that the research has been scattergun. "If we [continue to] do a study here, a study there, as we have for the last 20 years, it could take forever."
At a "Future of Male Contraception" conference, sponsored by the U.S. National Institutes of Health in Seattle, a variety of methods were reviewed, including:
Hormonal therapy and testicular warming -- Swerdloff and his team found that giving men testosterone and another hormone with testicular warming helped suppress sperm. "The transient testicular warming [like sitting in a spa] causes the suppression to occur much earlier [than the hormones alone]," he said. Transdermal gels -- In another study by Swerdloff's team, 140 men applied either a progestin gel called Nestorone or a testosterone gel, or both. The researchers studied various doses and then drew blood samples to measure hormone levels. They reported on the 119 men who complied and finished the study, concluding that the combination worked better to suppress sperm. "Intra Vas Device," or IVD -- An alternative to a vasectomy, this method involves inserting silicone plugs into the vas deferens, the tube sperm move through and the same tube cut in a vasectomy. "The sperm can't get past the plugs," said Joe Hofmeister, president of Shepherd Medical Company in St. Paul, Minn., the IVD developer. "Preliminary six-month data show that 90 percent of 60 men [tracked to date] have zero motile sperm," he said. More study is needed to track the IVD for reversibility, Hofmeister said. Vitamin A blocker -- Columbia University researchers tested a drug abandoned by a pharmaceutical company because it interferes with vitamin A receptors in the testes, lowering fertility. It worked well in animal studies; whether it will do the same in human studies is not yet known.
These approaches, if successful, will take several more years to get market approval, all the researchers agreed.
To learn more about all available contraception methods, visit the U.S. National Library of Medicine.
SOURCES: Ronald Swerdloff, M.D., professor of medicine, Harbor-UCLA Medical Center and David Geffen School of Medicine, University of California, Los Angeles, chief of the division of endocrinology, Harbor-UCLA Medical Center; Joe Hofmeister, president, Shepherd Medical Company, St. Paul, Minn.; Elaine Lissner, director, Male Contraception Information Project, San Francisco; "Future of Male Contraception" conference, Seattle