Why Is There No Male Birth Control Pill?S

Bet you didn't have this marked on your calendar: today is World Vasectomy Day, a holiday celebrated not with parades or fireworks, but with the delicate snip of two tiny tubes. But is such a largely permanent step really our only male birth control option? Where's the male version of the pill?

Surprisingly enough, research on oral contraceptives for both men and women kicked off more than a half century ago. The female variant was solved first, and has become a pillar of modern reproductive health; according to the CDC, nearly 82 percent of U.S. women surveyed between 2006 and 2010 used the pill, more than any other method by a long shot.

Meanwhile, a non-surgical, non-barrier form of male birth control eludes us, thanks to societal norms, squeamish pharmaceutical companies, and some confounding scientific challenges.

Failure to Launch

The Pill For Guys isn't here yet, but it's close. And it has been for fifty years, explains Elaine Tyler May, Ph.D., Regents Professor of American Studies and History at the University of Minnesota and author of America and the Pill: A History of Promise, Peril and Liberation:

"The push for male hormonal contraceptive goes way back, more than a half-century, when the search was going on for female contraceptives. Starting in the 1950's, researchers were saying it was just around the corner, within the next 5 years. That was repeated over the next half-century, up to and including today."

But while the mechanism behind the female pill has been tweaked to near-perfection, a hormone-based solution for males is still elusive "There have been a lot of almost insurmountable side effects for every compound tested," Dr. May told us. "The most significant is impotence—nobody wants to take a birth control pill that makes them impotent."

John Amory M.D., Ph.D., Professor of Medicine at the University of Washington, explained some of the hurdles particular to male birth control. "Hormone-based efforts work well in 80 to 90 percent of men, bringing their sperm counts down to zero. It's reversible and pretty well tolerated. The problem is, it doesn't work in all men, and we don't know why. And we don't know for three to six months if it's going to work [for a particular patient]. For those reasons it's almost made it to market, but hasn't made it all the way."

So the birth control pill for men exists. It's just potentially a nuclear option.

Hormones aside, the physiological challenges are daunting. As Dr. Amory points out, women release one egg a month, whereas men make 1,000 sperm every second. And while women's birth control tricks the body into a natural state of infertility (by boosting the hormones present when a woman is pregnant), there is no analogous sperm-free period to mimic in men. As for Dr. Amory's area of study—blocking an enzyme in the testis that turns vitamin A into retinoic acid necessary to produce active sperm—he says it's about five years away.

Naturally.

The Next-Best Thing

So a male version of the pill isn't hitting pharmacies any time soon. What else is out there? Well, there's the option of injecting gold nanoparticles into the testes, then zapping them with infrared laser until they get warm enough to kill sperm without damaging the surrounding tissue. Hypothetically promising, but so far only tested in mice.

Then there are ways to block the biological processes that make sperm, like Dr. Amory's retinoic acid inhibitor or similar methods that target proteins. Unlike hormone modulators, which can dial down libido and erections as they shut off sperm production, targeting specific mechanisms in the testis means no side effects elsewhere. But again, that vague five-year timeframe hangs in the air.

More recently, there's the very promising "reversible vasectomy," (BE WARNED, that link has one leg-crossingly graphic image) filling the vas deferens with a polymer mesh that breaks up sperm without blocking the flow of ejaculate. It's quick, cheap, fully reversible, and it's proven 100% effective in India. But it's been on a slow road to stateside approval. Human trials are slated to begin in 2014.

Our Best, Most Permanent Solution

This leaves us with the old-fashioned vasectomy, where the tubes are cut and rarely put back together. Akhil Das, M.D., assistant professor of urology at Thomas Jefferson University, says the whole thing takes about an hour in the office, and in eight weeks, after a confirmatory sperm count, patients are free to never worry about fatherhood again. "Reversal is challenging," he says. "It's unpredictable, and the expense to reverse is on the patient. If they have any doubts, if they're thinking about reversing, I don't encourage the vasectomy."

But Dr. Das says his patients are usually 100 percent set on a vasectomy when they reach his office. No turning back. And if they do have doubts, they might as well hold tight; I hear there's a great alternative that's just five years away.

Photo Credit: Shutterstock / Timolina & Hugo Felix