The name says it all. "Penis captivus" is the medical term for when the penis is essentially held captive by the vagina during sexual intercourse. It gets stuck, neither partner can separate the bond, and this is not a myth. But for as terrifying as it sounds, does its severity really live up to the hype?

The idea of a penis getting stuck in a vagina might bring to mind the 2007 film Teeth, a comically absurd horror film about a teen girl whose vagina houses teeth — described in folk tales as vagina dentata — which sever every unknowing man’s member, especially when he’s committed a wrong (in her mind). Thankfully, penis captivus isn’t as gruesome, as common, or as serious.

“When the penis is within the vagina, it becomes increasingly engorged,” Dr. John Dean, clinical director of gender and sexual medicine for the Devon Partnership NHS Trust in southwest England, recently told BBC Health Check. “The muscles of the woman’s pelvic floor contract rhythmically at orgasm… While those muscles contract, the penis becomes stuck and further engorged within [the vagina] until the muscles relax. Blood can flow out of the penis again, the penis starts to go down after orgasm, and the man can withdraw.” He also noted that the rhythmic contractions a woman experiences during an orgasm aren’t spasms — these usually characterize vaginismus, which can cause vaginal spasms so strong and painful that the vagina closes, according to the National Institutes of Health.

The fascination with penis captivus, Dean said, is the “prospect of a couple struggling to separate themselves for many minutes.” But he says that in his own experience, on the rare occasions that he’s heard of it, it only happens for a few seconds — between five and 10. Long enough that “if you’re in that situation that probably seems like an eternity.”

A Limited History of Penis Captivus

Although Dean passes penis captivus off as a mild occurrence, there have been reports of more severe cases, however, the condition is already so rare. Only a handful have been reported in the past century, and many were dismissed because they were “based on hearsay” with a “tenuous connection” to the “actual facts,” Dr. F. Kraupl Taylor, a physician, wrote in a 1979 article in the British Medical Journal (BMJ). But of the cases that he speaks about, he mentions a “more or less credible instance” from 1910, in which a pair found themselves stuck, and in “intense pain,” from attempts to separate. It wasn’t until the woman was given chloroform, which was once used as an anesthetic, that her vagina was able to release the man’s penis.

Another physician’s response to Taylor was published in BMJ in 1980. Dr. Brendan Musgrave’s letter spoke about a personal experience that occurred in 1947. At the time, Musgrave was a houseman at the Royal Isle of Wight County Hospital in south England, when a honeymoon couple was brought out of an ambulance “on a single stretcher.” The woman was also given anesthetic, and the couple were discharged.

Penis captivus occurs more frequently in animals than it does in humans, Dean said. And it’s not uncommon to see animals that “are stuck together after sex, particularly dogs … and people look on with bemusement.” If there was to be a more notable, severe case in humans that necessitated intervention or admission to a hospital, Taylor wrote, “it would have been eagerly reported in a medical journal with as much evidence and detail as possible.”