Soon after the birth of her first son, Danielle, a 42-year-old communications manager from Winnipeg, Canada, found she could no longer have sex without feeling like she was being torn apart.

“My husband and I would barely start penetration and it would just be excruciating. The whole area tightened up like a fist,” she says. “I had never had any previous difficulties, plus I'd had a c-section so I didn't think that area could be affected. It was like, 'Holy crap, that hurts! What happened?' We were both really taken aback.”

One commonly-suggested remedy is inserting a series of progressively wider objects to accustom the sufferer to the sensation of a foreign object in the vagina.

Danielle's gynecologist explained that her condition might be psychological in origin, and offered some tactics she could try to head off the very real physical pain. “She gave us suggestions like using a candle either in the shower or with lubrication. That felt very silly, so it didn't last long.” When the pain persisted, “I started to just grin and bear it and say, 'I can do this.'” But her husband, who could tell she was gritting her teeth just to get through the encounter, bailed out. “He said, 'No! Forget it!'”

Pain during sex affects millions of women, and the medical community's explanations for why it happens seem nearly as numerous. Gynecologists have treated sufferers with everything from vaginal insertions to Botox. Surgeons want to solve the problem with a scalpel. Psychologists prescribe anti-anxiety meds for it. Despite centuries of study, it's an area that remains in dispute.

Indeed, while vaginismus—the clamping shut of the vaginal muscles when a woman attempts intercourse—remains unfamiliar to most people, the condition has been reported for hundreds of years. In an 1880 edition of Archives of Medicine, J. Marion Sims, an American gynecologist who worked in Paris, reported, “I was consulted by Madame X... This woman had been married three or four years and consulted me on account of her sterility. She had complete vaginismus, and the marital relation was a physical impossibility.” Joyce Maynard's incendiary 1998 memoir, At Home in the World, describes the vaginismus she experienced in her relationship with reclusive writer J.D. Salinger.

Early psychoanalysts proposed that the condition was caused by some kind of mental resistance, conscious or not, to the idea of having sex. And this belief that the disorder has a psychological origin has persisted—vaginismus and its similar sibling, dyspareunia, which is a more general complaint of pain during intercourse, have long been included in the American Psychiatric Association's Diagnostic and Statistical Manual of Mental Disorders (DSM). Recently, some experts have proposed combining vaginismus and dyspareunia into a single diagnostic entity for future editions of the DSM, and calling it genito-pelvic pain/penetration disorder. “There was never any good evidence—and there continues not to be any—that we can tell the two disorders apart,” says Irv Binik, a psychologist at McGill University in Montreal who wrote an article in Archives of Sexual Behavior outlining the proposal. “Many women with pain have difficulties with penetration as well.”

But is genito-pelvic pain/penetration disorder really rooted in a psychological problem at all? To be sure, there is limited evidence that painful sex may have a mental-health link. In a small-scale study Binik and several colleagues published in 2003, women who had vaginismus were twice as likely to report being sexually abused during childhood as women in a control group, suggesting that the abuse might be linked to the condition for some women.

But many other psychodynamic explanations have little or no evidence to back them up. “People have said poor sex education or a religious environment not open to sexual information contribute,” Binik says. “Those are interesting ideas, but they don't pan out.”

“When you look at dyspareunia, to a gynecologist it's not a psychiatric condition,” says David Toub, an ob/gyn in Wyncote, Pennsylvania. “It can be due to any number of treatable causes, like endometriosis.” Often, he says, uncovering the physical causes of sexual pain takes a detailed assessment by multiple specialists. One patient who came to him, for example, turned out to have an extremely narrow vagina that he was able to correct surgically. “I don't doubt that my colleagues in psychiatry are well-meaning, but as a gynecologist, I think we have to be really careful.”

The biggest danger, Toub says, is that doctors could potentially use the diagnosis of genito-pelvic pain/penetration disorder as an excuse to dismiss as psychological a condition that may actually have a physical origin. Take Stacie, a stay-at-home mom in Nova Scotia, Canada, who's struggled with sex-related pain for years. She says that she’s seen a shrink who convinced her that her problem was simply a symptom of anxiety.

“Doctors automatically think it's stress,” says Stacie. “They say, 'You're too stressed out, just relax.' I've seen a psychiatrist and all he really wanted to do was to prescribe pills.” She's tried a handful of different antidepressants to no avail and is skeptical of the idea that she has a psychiatric condition. “I have no doubt that there's something physically wrong with me,” she insists. “I know it's not in my head.”

Binik doesn't think the idea that pain during sex might have psychological roots should serve as license for providers to write it off. “I don't have much sympathy for doctors who say, 'It's all in your head.' If it's used in a dismissive sense, that the pain doesn't really exist, that's very unfortunate.” But he still believes that some type of pain/penetration disorder is worthy of inclusion in the DSM, an assessment bolstered by the fact that cognitive-behavioral pain management, a form of psychotherapy that focuses on relaxation and mental control techniques, has been shown to reduce pain during sex significantly.

But since talk therapy doesn't work for every sufferer, a range of other treatments of varying effectiveness have been tried. One of the most controversial is Botox. In a 2004 study by Shirin Ghazizadeh at the University of Tehran, 18 of 24 vaginismus sufferers were able to have relatively pain-free intercourse after a single series of Botox injections to the pelvic region. (Binik cautions that it's difficult to assess the reliability of studies like this because they do not contain a control group.)

Top Chef host Padma Lakshmi, for her part, has campaigned to raise awareness of endometriosis, a disorder that occurs when the uterus lining fails to expel during a woman's period, and which can also cause painful friction during sex. Endometriosis sufferers sometimes take as long as ten years to diagnose—Lakshmi didn't know she had it until she was 36, and required four surgeries to treat it.

For some women, exercises that strengthen the pelvic muscles soothe the discomfort associated with sex, and occasionally, surgery to remove a small section of the vulva called the vulvar vestibule helps. “It relieves the pain for a large number of women,” Binik says. “I don't have a clue why.” Another commonly-suggested remedy is similar to the one Danielle's doctor prescribed: inserting a series of progressively wider objects to accustom the sufferer to the sensation of a foreign object in the vagina. This treatment, however, only works for about one-quarter of women.

While the suggestions Danielle's doctor offered proved futile, her vaginismus went away after she stopped breastfeeding. She thinks the hormonal shifts that occur with pregnancy and breastfeeding might have contributed to her condition—a belief that grew stronger after the birth of her second son, when the vaginismus roared back with a vengeance. “The second time was not as bad, because I knew about the condition, and maybe I was expecting it. But again, it took almost six months to get things feeling back to normal.” She advises women with similar issues not to settle for glib explanations. “You have to advocate for yourself. If a doctor tells you it's all in your head, go find another doctor, because it's not.”

Elizabeth Svoboda is a writer in San Jose, California. She contributes to Discover, Popular Science, and Psychology Today.