When British television aired a story about a woman who had been born with double the equipment - two vaginas, two cervixes and two uteruses - Internet commenters piped in and said, "Me, too!"
Hazel Jones, a 27-year-old from High Wycombe, has a rare, but not unheard of condition called uterus didelphys, which is not easily diagnosed until a woman's sex organs develop as she enters puberty.
"It's not that crazy at all, even though it sounds like a sci-fi thing," said Vincenzo Berghella, director of maternal fetal medicine at Thomas Jefferson University in Philadelphia. "We see many couples, maybe one a month or more."
Jones, who got her diagnosis at 18 after suffering for years from menstrual cramps, shared her story this week with ITV's show "This Morning."
"I thought it was amazing and it's definitely an ice-breaker at parties," she said. "If women want to have a look, I'm quite happy to show them, it's not something I'm embarrassed by."
Jones has a septum or dividing wall between her two vaginas, which occurred during her own development in the womb, say her doctors. The condition occurs in about one in 3,000 women, according to the World Health Organization. Women can have children, although they are more apt to require a C-section section, as babies are often born breech.
A variety of uterine or mullerian anomalies occur in about 1 in 200 births, according to Berghella. "You do the math - probably more than 100 million women in the world have it."
"The reproductive tract is made of two tubes next to each other all the way from the vagina to the fallopian tubes," he said. "They are supposed to fuse at the level of the vagina so they are only one. For whatever reason - it's unknown - the two tubes don't fuse and you have double. There are more than 10 variations and sometimes you have two uteruses."
Often it is diagnosed when women have reproductive or infertility problems, but some women may go on to have children and never know they had the condition, said Berghella. Surgery can also repair a vagina with a septum, though scarring or perforation can occur.
Jones first suspected something was wrong when her boyfriend told her that her genitals were "different." She also found sex uncomfortable and wonderered why her girlfriends were baffled when she asked "which hole" to use with tampons.
Others who read the online story this week said they also had the condition.
"I have had a successful pregnancy with the only 'problems' being that my baby was breech resulting in a scheduled c section however ending up being an emergency as I went into labor and interestingly the left cervix dilating even though the pregnancy was in the right womb," wrote GA of East Sussex wrote the Daily Mail newspaper. "How interesting is the human body?"
Another, AMS of Cheshire , said that like Jones, she "lost my virginity 'twice" before being diagnosed at 21 due to the doctor not being able to perform my first smear and having the septum cut to make one vagina.
"I thought something terrible was wrong with me but have learned it is quite common," wrote AMS, who said she'd had two children - one in each uterus, after several miscarriages. "There are much worse things to suffer from."
Last year ABCNews.com interviewed Kelly Miller of Hagerstown, Md., who had appeared on TLC's series, "Strange Sex."
Miller, then 28, said she also had excruciating periods before she was diagnosed with uterus didelphys. She had first appeared on the Tyra Banks show in 2005 with other women who had two vaginas.
"[Banks] told me she wanted to do the show to let other girls know it's actually more common that what people think, but most women are not eager to talk about it," Miller said.
Later other women thanked Miller for being so open. "They said they felt more comfortable," she said. "It shows that women, even if they have the condition, can have a perfectly normal marriage and have children."
Miller's vaginal opening is a thin wall of skin that separates into two cervixes that lead to two separate uteruses. Her right one is dominant. The left vagina is only pencil width and is nonfunctional.
Each of her uteruses was 60 percent the normal size and might not accommodate the growth of a fetus if she got pregnant, Miller was told by her doctors.
She was put on a low dose of birth control pills to regulate the double monthly bleeding, even though she was not sexually active. Then in 2002, she met her future husband.
"I didn't tell him at first," she said. "I worried he would think I was weird. But there's nothing about me that would make things sexually different."
Miller soon got pregnant. At 37 weeks, Miller successfully delivered a girl, and in 2005, delivered another healthy daughter.
"The doctor said I was very, very lucky," she told ABCNews.com.