For now, men who want to do their part for birth control have meagre choices: a vasectomy - meant to be permanent - and condoms.
For years, experts have predicted that more choices will be here soon. That time is getting closer.
At a Future of Male Contraception conference sponsored by the US National Institutes of Health in Seattle, a variety of methods were reviewed, including:
- Hormonal therapy and testicular warming. Researcher Dr Ronald 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.
- The "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, Minnesota, 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.
"It has been slow," said Swerdloff, chief of the division of endocrinology at Harbor-UCLA and professor of medicine at the Harbor-UCLA Medical Centre in Los Angeles. Among reasons for that slow pace (and Swerdlow was not commenting on the fact that most men would rather leave contraception up to women) is the fact that pharmaceutical companies are reluctant to take on a new product quickly because of untested liability issues. And "one of the biggest single issues has to do with the fact that contraception in general is a difficult area: it is used by large numbers of healthy individuals". The safety threshold, he noted, is high.
4 or 5 years
"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 organisation.
Research has been scattergun, she said. "If we [continue to] do a study here, a study there, as we have for the last 20 years, it could take forever." – (HealthDayNews)