Here’s What Happens to Your Sperm After You Donate It There’s a good chance it travels to the U.K. to make British babies “It’s better when it’s fresh,” Ari Nagel explained to the New York Post in June, emerging from the men’s bathroom at a Brooklyn Target looking a little flushed and quite pleased with himself. Nagel, aka “The Sperminator,” a 40-year-old CUNY Kingsborough math professor, has fathered a number of kids by jerking off in NYC bathrooms and immediately handing over the specimen to an ovulating woman who inserts it into her cervix within 12 hours. He and the mothers-to-be also sometimes conceive the old-fashioned way, with a few lesbian couples holding their partner’s hand in bed for moral support. Across the pond, Simon Watson, a British man believed to be the world’s most prolific sperm donor, estimates he’s sired at least 800 children over the last 16 years but admits the figure could be closer to 1,000. Watson finds his clients on Facebook and offers women what he describes as his “magic potion” for £50 directly, saving them thousands by bypassing expensive and lengthy IVF and fertility treatments. But what about all the unfamous, run-of-the-mill sperm? You know, the stuff your college buddy used to donate once a week to afford a few rounds of Natty Light and shitty pizza? Are his progeny now overrunning college-town daycare centers? Or are vials of his less-than-magic potion stacked in a cryobank somewhere gathering dust like miniature, depressing fish tanks? We consulted some sperm experts to find out. Sperm for Dummies First, let’s take a step back. A lot of people wrongly assume sperm is made during sex or masturbation and exits the body in a matter of minutes. Sperm, however, is actually initially created in the testicles during a process called spermatogenesis and then proceeds to the epididymis. “We call that ‘sperm school,’ ” explains Mel Cohen, a specialist at the Fertility Center of California in San Diego. “It’s where the sperm learns how to swim and how to break the shell of the egg.” There, the sperm cells mature for approximately two to three weeks, after which they travel through the vas deferens to the seminal vesicle, a waiting room of sorts, where they hang tight until an ejaculation occurs. In total, it could be anywhere from 70 to 90 days before they leave the premises, whether their creator is ejaculating frequently or not. Then It’s a Volume Game The average man shoots between 1 and 5 milliliters of ejaculate every time he orgasms; for every milliliter he produces, there should be a minimum of 20 million sperm. A donor needs two days of abstinence to ensure the tanks are full, but no more than five days. “Most guys have a perfectly adequate specimen to produce their own children,” explains Scott Brown, director of client experience and communications for California Cryobank, “but we look for guys in the top 15 to 20 percent of the general population. We want the all-stars, the best of the best.” The sperm need to be Phelps-ian swimmers, too. “Then we look at morphology to make sure they don’t have two heads, two tails, or the tails are so long they won’t get to where they’re going.” There are additional tests for drugs, alcohol, even tobacco. If the donor still qualifies, they move to the next step: repeating the exact same thing five days later. A Leper Colony for Sperm The handful of sperm that manage to make it this far are rewarded with a six-month quarantine, during which the specimen is relentlessly tested for any STDs that might have been dormant the first dozen times they checked. Lockdown is no joke. “You need fingerprints to gain access to the storage room,” Brown notes, “which is set up with tanks and cross-referenced with a manual and computer system.” Everything is also videotaped, live-streamed and recorded, and in San Diego at least, there are extensive safety measures taken for earthquakes. “It’s human tissue,” Cohen says, justifying the increased security measures. “What’s human tissue worth? I’d hate to be the one who had to go to court to find out.” The Deep Freeze The good samples are “washed” in a centrifuge that removes blood cells, seminal fluid, anything other than live sperm, and cryogenically frozen in liquid nitrogen. “Remember in Terminator 2 when he spills the tanker truck over him and freezes solid into a million pieces?” Brown asks. “That’s liquid nitrogen.” Biologists believe that correctly frozen cells in long-term storage can last forever, as long as the temperature — minus 196 degrees centigrade (minus 320.8 degrees Fahrenheit) — is properly maintained. All biological activity is effectively stopped at that point and the sperm is truly in suspended animation, Brown says. Bacteria or other microbes cannot attack or degrade it because they’re unable to function at such a low temperature. The oldest swimmers in the tank? “About 35 to 40 years old,” Cohen says. His boss, vasectomy doctor/surgeon Martin Bastuba, purchased Sperm Bank Inc. 20 years ago, fully stocked with decades’ worth of sperm. Cohen admits they “haven’t identified an expiration date but as long as it stays constantly frozen, it should be good once thawed.” Anecdotal evidence seems to back him up: For instance, a woman gave birth to twins in 2011 after being successfully impregnated with 40-year-old sperm frozen by a Japanese-American war hero in 1971. .