Doctors have warned that “The perilous position” — also called ‘female superior’ — is known for its risk of injuring an erect penis.
This position can be described as having sex in the reverse cowgirl position. In other words, it occurs when the woman is on top and faces away from her partner.
Although there are no bones in the penis, the injury is still known as a ‘fracture’.
Writing in the journal Urology Case Reports, doctors noted that, as well as during sex, penis fractures can also happen during masturbation or even by turning over in bed at a funny angle.
The urologists explained that the ‘very uncommon urological emergency’ is easy to recognise and diagnose, as they generally cause a cracking sound, sudden swelling, bruising and severe pain.
It may also be difficult to pass urine and the penis may bleed.
They noted that surgery results in the fastest recovery.
There have only been around 16 documented cases of the injury per year worldwide since 1925.
Men in their 40s are most likely to experience a penis fracture.
The anatomy of an erection is based around two spongy tubes which fill up with blood and harden, and a firm, fibrous sheath which surrounds them, called the tunica albuginea.
When the tunica albuginea, which is made mostly of collagen, comes under extreme pressure it can snap and cause the penis to bend out of shape.
This followed the admission of a man who fractured his penis after it buckled against his partner while having sex in the notoriously risky position.
The 37-year-old, from Indonesia, showed up to hospital with a swollen, bloody and severely bruised penis, which doctors said resembled an aubergine.
The patient explained that he heard a ‘loud popping sound’ while having sex a few hours earlier in the reverse cowgirl position — when the woman is on top and faces away from her partner.
Doctors found he had fractured his penis and rushed him in for emergency surgery, where they repaired the damage.
The medics have now issued a warning that the injury can occur when an erect penis hits the perineum or pubic bone of their partner during ‘vigorous’ sex — causing it to buckle.
Urologists at General Hospital of West Nusa Tenggara Province detailed how the patient showed up at the emergency department with a swollen penis, which he said started three hours earlier.
The man explained that he was having sex in the reverse cowgirl position when he suddenly heard a crack.
The man immediately felt severe pain, lost his erection and began bleeding out of his penis. The patient was also unable to pass urine.
Doctors said the patient had suffered a significant hematoma — an injury to the wall of the blood vessel, which causes blood to seep out into the surrounding tissue.
They noted that his penis was left with the ‘eggplant deformity’ — when it swells and turns purple — which is a tell-tale sign of a fractured penis.
The man was rushed into surgery, where doctors made an incision into the tip of his penis to ‘deglove’ it — when the top layers of skin and tissue are removed.
This revealed a ‘wide and deep fracture to the penis’.
Medics noted that the tissue around the penis — the tunica albuginea — was ruptured.
The procedure saw surgeons clean the site of the injury, repair the two ruptured tubes and stitch up his urethra.
Medics performed an ‘artificial erection test’ to ensure there was no leakage from the wounds and that the penis did not bend abnormally.
The penis was then stitched back up and covered with a bandage.