Medical Examiner

Can Masturbating College Freshmen Actually Clog a Shower Drain?

Each September, a hoax mocking 18-year-olds’ excessive masturbation circulates on the internet. But what does the science say?

shower drain.
You did what?  

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Put a bunch of 18-year-old boys together, and you may get an overload of testosterone. A prank that has been battering about college dorms for years now takes this too literally and pokes fun at the prodigious amount of semen college freshman inevitably produce—specifically, in the shower, when, uh, you know. The prank is to post an official-looking notice in a communal bathroom decrying the fact that the abundance of in-shower masturbation has created a buildup of semen so drastic it is clogging the drains.

Photos of the notices have been circulating on the internet for years now, with variations of the same note embossed with letterhead from prestigious colleges and universities all over the world: Georgetown University, the University of Pennsylvania, the University of Michigan, the University of St. Andrews, etc. Just last week, another image of one such notice posted at the University of North Carolina at Chapel Hill made its rounds again.

This particular notice, from Ehringhaus Residence Hall, asserts that masturbation in the showers is in violation of the Carolina Housing Code and that the drains “are not built to withstand semen.”

“Every year UNC spends thousands in maintenance because of the excessive amount of semen stuck in the pipes,” the notice reads. As extreme as that sounds, this one actually doesn’t even go as far as some other letters—UPenn’s warned that if the situation was not remedied, the staff would resort to DNA testing to find the culprit.

The notices themselves, of course, are fake—likely the result of upperclassmen hoping to make anxious freshmen even more sexually uncomfortable than they are.

“These signs were not authorized nor endorsed by Carolina Housing,” an email sent to on-campus residents read. “Please disregard the notice.”

But we couldn’t help but wonder … did this classic September trick have real-life origins? Is this actually something that colleges worry about each fall, or something abundant shower masturbators have experienced in their own lives? Could excessive semen actually clog a drain?

To answer these incredibly important questions, we first tried the people we were convinced would know—the maintenance staffs at colleges across the country. They’re the ones with front-row seats to a presumable semen onslaught. It turned out that they had better things to do than talk to us (fair). Of the more than 20 maintenance heads, college PR staff, and facilities teams we reached out to, none of them returned our calls. In fact, one university media relations official responded that he did not feel it would be “appropriate to pull someone away from his or her job for this.”

Next, we turned to the scientific literature. As it turns out, there appears to be very little research published on the direct effects of semen in shower drains (free thesis idea).

Other internet theories have noted that semen does feel stickier when it gets wet, though the reason for that has been elusive. A NSFW Claymation video about this phenomenon suggests that water might actually react with semen in some way to make it stickier, but it doesn’t propose a compelling reason of exactly why this would happen.

It’s also possible that semen simply feels like it’s stickier in the shower because it’s being compared with water. Either way, you can see why a freshman guy who perhaps has masturbated while bathing might notice stickier semen and worry about the dorm-bathroom warnings. But can semen, sticky or otherwise, clog a drain?

Nope, it cannot.

Abraham Morgentaler, an associate professor of urology at Harvard Medical School and the director of Men’s Health Boston, debunked the rumor for us once and for all. In an email to Slate, Morgentaler says that not only is semen never thick enough to clog a drain, but that 20 to 30 minutes after ejaculation, it will become a runny liquid and slide away:

When a man ejaculates, the fluid first comes out like a gel, with a certain amount of consistency that likely helps with fertility by allowing it to stay longer within the vagina than if it were a runny liquid.

For this reason, a semen analysis is never performed immediately on a fresh specimen. The lab technicians need to wait until it becomes a liquid, which takes 20-30 minutes.

As a rule, semen just isn’t thick enough to clog a drain. And after a short time it will become runny like water anyway.

Carrol Platz, an assistant professor in cell biology at Baylor College of Medicine and the founder of the International Canine Semen Banks, agrees: “In humans, normally the semen remains liquid and would not clog drains.” Other mammals, apparently, have rubbery semen, but if you’ve got chimpanzees masturbating in your showers, you probably have problems beyond drainage.

So shower masturbators, it looks like you’re in the clear.