After decades of promising breakthroughs, no male birth control has made it to market. Why is it so elusive?

Just days after Melbourne urologist Nathan Lawrentschuk opened up applications for a world-first clinical trial of a new form of male birth control, he had to close them again. “Every time we open the portal, it just gets bombarded,” he says.

The draw card isn’t money, study participants aren’t allowed to be paid. While some could be driven by the scientific cause or an odd desire to provide regular semen samples, Lawrentschuk believes it is something more straightforward: “It speaks to the fact that there is a huge gap in the market.”

In a world where birth control has long been the purview of women, the proposition certainly sounds revolutionary. A hydrogel that hardens after being inserted into the vas deferens, the same tube that is cut or closed in a vasectomy, blocking the sperm from exiting. Lawrentschuk calls it a “no scalpel vasectomy”, but it also differs in another crucial way — the gel is designed to dissolve on its own after about two years.

“There’s never really been anything like it in the market,” says Lawrentschuk, who is the principal investigator on the ADAM study. “A lot of men would like to be in the driver’s seat when it comes to knowing they’ve got full control over their contraception, and there’s really been no product to date, other than having a permanent vasectomy, that’s allowed them to do that.”

Professor Nathan Lawrentschuk during the first insertion of the hydrogel that researchers say acts as a “no scalpel vasectomy”.(Supplied: Epworth HealthCare)

The study is currently in its second of three years. If successful, it will mark a major turning point in a decades-long saga marred by a slew of promising starts and just as many disappointing stops.

Since the female contraceptive pill was introduced more than 60 years ago, scientists have sought a similar solution for men. But as new contraceptive technologies have flowed onto the market for women, options for men have remained elusive. Today there are just two options: condoms, with a real-world failure rate of around 13 per cent, and permanent vasectomies (reversals exist but are expensive, costing up to $7,000, and are not guaranteed to work).

This is despite headlines regularly declaring imminent breakthroughs. In recent years these include the trial of a non-hormonal male pill known as YCT-529, a compound that blocks an enzyme sperm need to swim that has shown great promise in mice, and a topical gel that when rubbed on men’s shoulders once per day temporarily lowers their sperm count.

“It’s been ‘five years away’ since 1975,” says Professor Robert McLachlan, an endocrinologist and leader in male hormonal contraceptive research. “If you’re asking me when it’s going to be at the local chemist? Well a very, very, very long time, if at all.”

The reason for this delay, according to some experts, is not unresolved science — but money.

A disappointing history

“I’ve given basically the same interview in 1993, 2003, 2013, and 2023, and unfortunately nothing much has changed in the past 30 years,” McLachlan says. “Except we do know, spoiler alert, that it works perfectly well.”

Male birth control research is largely split into two camps: hormonal solutions, that stop or slow sperm production and in many cases mirror the well-established female oral contraceptive pill, and non-hormonal technologies that may impact sperm production, its movement out of the body (sperm transport) or its ability to swim (sperm motility).

Professor Robert McLachlan is hopeful that a hormonal male birth control could eventually make it to market. (Supplied: Robert McLachlan)

McLachlan began work on the former in the 1980s, decades after a “male pill” was first proposed. In his view, the science is settled — it works at preventing pregnancy, at least as well as its female equivalents. What went wrong is everything else.

By the 1990s, research into the use of testosterone to reduce sperm numbers was underway. With weekly injections, the majority of men’s sperm counts dropped to “almost zero” and pregnancy rates were on par with what you would expect from existing contraceptives, McLachlan says. In other words, it worked, but the trade-off was side effects including acne, weight gain, and mood swings — symptoms that might sound familiar to many women on the pill.

Researchers then tried lowering the testosterone dose and adding progesterone and “lo and behold, 95 per cent of those men got sperm counts of zero or less than a million, which was so low as to give a reasonable level of contraceptive cover,” McLachlan says.

The crescendo came in 2011 when the World Health Organization sponsored an international study into the use of this hormone combination as birth control. More than 300 men in monogamous relationships from around the world began receiving an injection containing the two hormones every 10 weeks.

But some participants reported mood changes, depression, and pain at the injection site. The WHO pulled the plug, concluding that the “risks outweighed the potential benefits”.

“The whole thing crashed like a house of cards,” says McLachlan, who co-authored the report on the study. “Not because it doesn’t work, because the social, geopolitical, pharmaceutical, environmental, litigious environment in which we currently live meant everybody pulled out.”

Research into a male birth control pill has been going on since the female contraceptive pill was released in the 1960s, but so far no trials have been successful. (Unsplash: Melany Tuinfosalud)

By the end of the prematurely aborted trial, 75 per cent of participants said they were satisfied with the method and willing to use it again if it became available. McLachlan says there’s no way to know whether the mental health issues were related to the hormones, given how common depression is. This is one of the challenges inherent to trialling contraceptives: you can’t have a control group as placebos don’t prevent pregnancy.

“I remember the pharmaceutical people saying at the time, ‘Listen, guys, we love you all and we get this, but here is the reality: it’s very, very expensive to continue with it now, there are concerns about whether the side effects are true or not, the marketability, the drugs are probably not patentable … how would there be a recoupment of investment?’,” McLachlan says.

“It basically killed the field.”

The funding gap

“I wasn’t a six-year-old saying I want to work in male contraception when I grow up,” Heather Vahat laughs over the phone from Durham, North Carolina, where she heads up the Male Contraceptive Initiative.

Instead, her career began at a not-for-profit working with female contraceptive development, during which time she travelled throughout India and Kenya to ask women what they wanted from their birth control. “And the women kept saying, ‘What about developing methods for men? That would be a great method for women.”

The Male Contraceptive Initiative (MCI) was created to push for greater male contraceptive choice and now provides funding for international research into non-hormonal options. The not-for-profit has so far given more than $12 million in research grants for the development of non-hormonal, reversible male contraceptives, making them one of the largest funders of male birth control research.

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