New research suggests that ultrasound can zap sperm. But does it really work, and what other alternatives might there be for men?
It was news that made many men cross their legs and click quickly away to another story.
A new study has revealed that ultrasound may, in future, be a reliable form of male contraceptive. The research – from scientists at the University of North Carolina – found that a short zap of high-frequency sound waves, directed at the testicles, killed a significant number of sperm in rats.
If the results were repeated in humans, the ultrasound blast would reduce sperm levels, “far below levels normally seen in fertile men,” said lead researcher Dr James Tsuruta.
More research is needed, but could this be the cheap, reliable, reversible and side-effect-free contraceptive men have been waiting for? And would you be man enough to try it?
It’s fair to say that science has been searching for a male equivalent to the female contraceptive Pill for decades, with any number of false dawns along the way. Newspapers regularly report that a hormonal male Pill is just around the corner, but none has so far made it into the pharmacy.
That’s partly because using hormones to stop billions of sperm is a trickier undertaking than stopping one monthly egg. Using hormones to make men temporarily infertile is a tough ask and it could also be an unpopular one. As women have found, hormonal contraceptives have unpleasant side effects. Knowing that, do men really want a hormonal Pill?
“We don’t need to put men through what women went through for pill development in the 1960s,” says Elaine Lissner, director of the Male Contraception Information Project (MCIP). “Men won’t put up with it, and they shouldn’t. Times have changed.
“Hormones are not one-size-fits-all. You see this with the pill. Women often go through several attempts before they find one that’s just right for them – or at least tolerable! Why manipulate a system that affects nearly everything from A to Z – acne, blood pressure, cholesterol, you name it – when you can take a more targeted approach?”
The ultrasound method is a good example of just such a targeted approach.
The question is, will it work?
In fact, the North Carolina study is just the latest of a string of studies on the efficacy of ultrasound as a male contraceptive dating back to the 1970s. Studies have been completed on rats, dogs and monkeys. The equipment is readily available. Ultrasound does appear to zap sperm.
“It’s clear now that ultrasound works, once you get the settings right,” says Lissner. “That said, it will take a lot more research before the average man will feel comfortable with it for temporary contraception.”
And that’s the problem. There are two serious questions that need to be answered before ultrasound is accepted as a bona fide male contraceptive. Put simply, if ultrasound zaps sperm, how long does it take for fertility to recover? And what effect will repeat doses of ultrasound have on sperm quantity and quality in future?
“How well will fertility return after many uses in a row? And would there be issues with sperm quality, and possibly birth defects, while it is wearing off?” asks Lissner. At the moment, she believes ultrasound may have more potential as a permanent method, a nonsurgical alternative to vasectomy.
That might change with more research, but research requires funding, and the problem with ultrasound – and other non-hormonal contraceptives – is that there’s little profit to be made. Companies would prefer to sell men (and women) an endless supply of pills than a one-off ultrasound machine. The search for reliable male contraceptive options is a long road.
The ultrasound study does at least show is that there may be realistic alternatives to a hormonal pill many men would be reluctant to take, and the less-than-ideal methods – condoms, vasectomy, withdrawal – currently available.
According to Elaine Lissner, a different, plant-based pill called Gandarusa is in advanced clinical trials in Indonesia and could be available there soon. “But the first new method to win regulatory approval in the west may be Vasalgel, a polymer gel with a microscopic mesh structure that directly filters out the sperm as they flow through the vas deferens tube,” she says.
Another promising method is a pill being developed by a team at Kings College, London, which prevents the vas deferens (the tube sperm pass through) from contracting and pushing the sperm out during ejaculation. “It has a side benefit that ought to be of great interest to AIDS funders but has so far escaped notice: it could greatly reduce the male-to-partner transmission of HIV,” says Lissner.
None of these options – or indeed a hormonal male pill or patch – is likely to be available in the very near future, however. The makers of Vasalgel – a non-profit organisation – hope to have it on the market in the west within four years.
But there is some cause for optimism. For many years policymakers didn’t think men were interested in contraception, but even with current options, men now cover more than a third of contraception in developed countries.
That may be the most important message from recent developments. Whether it’s ultrasound or anything else, young men want more of a say in the contraception they and their partners use, and they also want more – and better – options.