Doctors in Boston report that a young woman began producing milk, apparently because her nipple rings stimulated her breasts into thinking she was nursing.
This is believed to be the first time that anyone has reported a connection between body piercing and lactation.
"I suppose women should realize that this is a possibility," says Dr. Geoffrey Modest, a family practice doctor and clinical professor at the Boston University School of Medicine. "If they start lactating, they probably should see a physician just to check it out."
Modest and a colleague wrote about the case in a letter to the editor in yesterday's issue of The New England Journal of Medicine (news - web sites).
According to their report, a 20-year-old woman went for medical care three weeks after getting her nipples pierced because she was experiencing pain and discharge. She later returned because both breasts were producing milk even though she wasn't pregnant.
Tests showed her body was producing very high levels of prolactin, a hormone associated with milk production, Modest says. While the level itself was not unhealthy, it can often signal a breast tumor in a woman who isn't pregnant, he says.
In this case, it appeared the nipple rings -- along with an infection -- stimulated the breasts into producing milk. The woman, who later became pregnant and had an abortion, recovered after the rings were removed.
The Boston University doctors' explanation of the woman's case makes sense, says Dr. Lester B. Mayers, sports medicine director at Pace University in New York, who has studied body piercing.
"There's a complicated reflex that goes on with nursing and lactation," he says. "Lactation is stimulated by sucking, so the nipples obviously have receptors. One could visualize that if it's in the right tissue in the breast, the mechanical stimulation caused by a piercing could activate that reflex."
Last year, in apparently the first study of its kind, Mayers and colleagues surveyed 454 Pace students about their body piercings. Sixty percent of female students reported piercings in body parts other than their ears, including nipples, belly buttons and tongues.
Of the male students, 42 percent had piercings of some type.
The study also found that a large percentage -- 17 percent -- reported infections as a result of their piercings. However, the medical problems were usually not serious.
Cleanliness is the main problem, Mayers says, especially for navel piercings. "If you have an open wound which heals slowly, and a bacteriologically dirty spot, it's very logical that that would become infected," he says.
Nipples don't appear to be an especially risky spot for infections, but they probably pose more problems than earlobes, Mayers says.
The Pace study found that 5 percent of the women had nipple piercings, as did 1 percent of the men. Twenty percent of those with nipple piercings reported medical problems, typically bleeding.
People with new piercings should wash the area two or three times a day with antibacterial soap, Mayers says. Peroxide and alcohol should not be used because they will only irritate the area, he says.