The world of contraception might soon have a new participant — if the upcoming trials are successful. And this one’s for men. No longer restricted to the old-hat condoms (ugh) or vasectomies (ouch!), men might soon catch up to their female counterparts if upcoming tests of a hormonal gel show it’s effective in reducing sperm counts.
The gel, which has to be applied daily, contains two synthetic hormones, testosterone, and progestin. Topically applied progestin will decrease the production of a man’s own testosterone, and the added testosterone balances the deficit caused by the progestin — but not in amounts that will stimulate normal sperm production.
According to a recent news account, couples from several countries will test the new gel. It’s rubbed on the upper arms and shoulders daily. In an initial study, using the two hormones in separate gels, they completely halted sperm production in about 80 percent of the men testing it. For nearly 90 percent, sperm counts were less than one million per cc (which still sounds like a lot, but is unlikely to cause pregnancy — 15 to 20 million are considered necessary).
There have been previous attempts to fashion hormonal birth control for men. But in one case, a trial of an injectable form was stopped early because of serious side effects. And another trial of a different injectable hormone, testosterone undecanoate, seemed to be successful in Chinese men but has not been developed further.
And of course, an injectable treatment is less than ideal. Using a gel would be more comfortable and more likely to meet with men’s approval. And perhaps a future formulation might be implantable, which would remove the necessity of remembering to use it every day.
The trial of the new gel will involve men using it for four months while their sperm counts are monitored. During that time their partners will continue to use their usual birth control. When sperm suppression is successful, the partners will go off their birth control, and pregnancy rates (if any) will be assessed.
Whether or not this new gel is effective in reducing unwanted pregnancies, it’s crucial to remember that it will still be the case that only condoms are effective in preventing the spread of sexually-transmitted diseases.
