If you’re a woman and are distressed by your chronic disinterest in sex, you’re not alone. The condition is called hypoactive sexual desire disorder (HSDD), and it affects about 10 percent of women across all age groups, according to the International Society for Sexual Medicine. Here, RH chats with Nanette Santoro, MD, the professor and chair of the Department on Ob-Gyn at the University of Colorado at Denver. She fills us in about the condition that was once—but is no longer—considered a psychiatric disorder.

What qualifies HSDD as a disorder?

One of the distinct features [that classifies] HSDD as a disorder that requires treatment is whether or not a woman is bothered by the condition. So if a woman is not that interested in sex and she doesn’t have a partner and there is no real consequence to her, then there wouldn’t be a problem that requires treatment. This is one of those conditions that, if it’s bothersome enough to the woman, then it is a disorder.

How does sex drive differ from woman to woman, and how do you define what’s “normal”?

Well, when you look through different surveys of women of different ages, there’s a prevalence of 40 to 60 percent of women who have what’s called sexual dysfunction, which can be any one of a number of problems, among women at every age. The relative proportion of the problem that you’d blame on low desire seems to go up with age—not insanely dramatically, but it does go up with age—and the proportion of the number of women who are bothered by it was the subject of a recent study done by Janet Shifter, at Massachusetts General Hospital. So it does seem that there is some increase in HSDD as a complaint from women. I expect that’s partly based on societal expectations about what women should want or how they should participate in sex. How much of these complaints are innate to women is not so clear.

There seems to be a distinct physical versus psychological aspect to discussions about sexual drive disorders. How do you feel about that?

Everything that a doctor might see or a doctor would evaluate is really from a woman’s perspective about what’s going on. There are some physical conditions that you can measure, [for example] when women experience less sensation in the area of the pelvis, clitoris or the vulva. Women with some nervous or neurological conditions can have that problem, or women who ride bikes too much can pinch the nerves in those areas and actually reduce sensation. I would tend to blur the boundaries between the physical and psychological because [there’s often not a clear distinction]. If a woman feels less sensation, it could be because of changes in her tissues. But the one thing that I would say is unquestionably a physical change that happens to women undergoing menopause is the vaginal tissues get drier because of estrogen loss, so that some women will experience sexual pain and that makes them averse to having sex. Fortunately, that is one of the easiest things to fix because a little bit of estrogen goes a long way and that’s often the type of thing that’s one or two office visits. You have a very happy patient who comes back in two weeks and says, Problem solved.

Very often women are made to feel less feminine, or that they are not “normal” unless they are having sex every day. This often causes some women to believe that they have a problem. How does this figure into this discussion about low sexual desire disorder.

I agree with what you say, and I think it’s key. The two most important things I have to contend with when I have a patient who presents with HSDD is that this is a relationship issue. One sexologist says that there is no drug in the world that will get a woman to enjoy sex with someone she hates, or someone she does not love, and that’s part of the problem. A lot of women are left to deal with their relationship issues, or those issues are so chronic and long-standing and they’ve become so used to them that they don’t recognize them as problems. Then, all of a sudden, sex falls off the cliff, and never comes back. Another is the expectation that women are supposed to be sex kittens from the day they become pubescent. For example, you have little girls doing the Beyonce dance when they’re 9 years old on YouTube, maybe even before the child is pubescent. This sex kitten imagery is not realistic. There are changes with age that affect sex drive and sexual response. People need to become more flexible and accommodate themselves [to these changes] and enjoy what they’ve got going on. That can happen, but this requires a lot of thinking, a lot of talking and some work with a sex therapist. But for most people, a pill seems like a much more attractive option, so that is what the drug companies want to provide. So far the drugs that are available [to address HSDD] seem to have a relatively small effect [and they might come] with unknown side effects that can happen down the road. That’s why women would do well to be very cautious about what drugs they take and consider what risks these meds may create.

Is drug treatment ever an effective way to boost a woman’s sex drive?

There really isn’t anything out there that’s approved. There are off-label treatments, but the one that’s been studied the most—testosterone—isn’t really ready for prime time. Some patients swear by that hormone, and they’re willing to take on some of the unknown risks in taking it. But those kinds of patients are rare. But I think one of the things that women really need to be careful about is when doctors offer to test their hormone levels and replace hormones they say will make their problems go away. There’s no rational [principle] to measuring hormones and, currently, there’s not an effective way to identify a particular hormone as the culprit responsible for a low sex drive. The other thing that’s key is for menopausal women who feel a loss of sex drive or a loss of sensation is to ask their doctors about estrogen because that has a stronger relationship to sexual function than testosterone does. Although many women may shy away from estrogen and think it’s bad for women’s health, we know far less about testosterone.