In 2010, a young Filipino celebrity couple was the subject of speculation because of rumours that they were rushed to a big Philippine hospital in a vaginal lock while lovemaking.
The young couple, Shaina Magdayao and John Lloyd Cruz, denied being in that situation.
Dr Anstomenis Exadaktylos, a Switzerland- based physician and author of a study covering 11 years of emergency hospital admissions, believes stories like that are probably urban myths.
However, BBC, in a report for Health Check, wrote about two couples who had real-life experiences of the medical phenomenon called penis captivus or captive penis, which another Britain-based sexual doctor found credible example of a rare occurrence.
Dr John Dean, clinical director of Gender and Sexual Medicine for Devon Partnership NHS, quoted by BBC, explained, "When the penis is in the vagina it becomes increasingly engorged ... the muscles of the women's pelvic floor contract rhythmically at orgasm. While those muscles contract the penis becomes stuck and further engorged."
An anonymous female BBC listener wrote of such an experience between herself and her late husband wherein he could not withdraw his organ which was stuck inside her vagina due to the intensity of the vaginal muscle response when she had an orgasm.
The second account came from a man who used the pseudonym John. He initially recounts hearing a story when he was a teenager of an American airman who was the victim of penis captivus, requiring the embarrassed couple to be rushed to the hospital in an ambulance to separate them.
When he became a sailor, he had an on-off relationship with a woman in Japan, and they experienced the vaginal lock too. He recounted it took them two to three minutes of movements and laughing as well before they become disengaged.
Mr Dean confirmed the experience of John, now 75, explaining, "The fascination is with the prospect of a couple struggling to separate themselves for many minutes, what actually happens in that they may find themselves in difficulty disengaging for maybe a few seconds - five seconds, ten seconds, and if you're in that situation that probably seems like an eternity rather than just five or ten seconds."