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.
More information
To learn more about all available contraception methods, visit
the
U.S. National Library of Medicine.
