All sorts of factors, from age to relationship status, can influence whether you crave sex…or would rather clock an extra hour’s sleep. But when does a low sex drive become a disorder?

It's mostly a matter of how you feel about your libido level. Some people don’t mind having a low libido, Lauren Streicher, MD, a clinical professor of obstetrics and gynecology at The Feinberg School of Medicine and the founder and medical director of the Northwestern Medicine Center for Sexual Medicine and Menopause, tells Health. “The element of it that makes it a disorder, as opposed to low libido, is that it’s upsetting to her."

A word on terminology: you may hear this disorder referred to as hypoactive sexual desire disorder (HSDD) or as female sexual interest/arousal disorder (FSIAD). Why two terms? In 2013, the most recent edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM–5) ushered in FSIAD in place of HSDD.

“They did that because a lot of the time, there was a conflation between people having sexual interest issues and arousal disorder—that’s not always true, but they do tend to overlap,” Nan Wise, PhD, cognitive neuroscientist, psychotherapist, certified sex therapist, and author of the forthcoming book, Why Good Sex Matters, tells Health.

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What causes hypoactive sexual desire disorder?

Pinning down precise numbers of how many people have this disorder is challenging. According to an April 2016 review of decades of studies and research on HSDD, 8.9% of women between ages 18 and 44 have HSDD.

“What we know is that many women who go to the gynecologist don’t bring it up because they’re not aware there’s a solution,” says Dr. Streicher. And many doctors won’t ask, she notes. Inquires about sex life are often contained to asking, “Are you sexually active?” and “What form of birth control do you use?” without touching on desire and arousal.

There are many factors that impact libido, says Dr. Streicher. “We know there’s a biological basis to HSDD that has been well studied with MRIs of the brain and looking at neurotransmitters,” says Dr. Streicher. Some medications—such as antidepressants—can put a damper on libido, as can certain illnesses. Psychological issues, relationships, and your environment also can contribute. “The higher our everyday, ongoing stress, the more likely that the access to lust is going to be depleted. Stress hormones are not helpful in that department,” says Wise.

A lower libido can be personally distressing—it can also have an effect on a person's relationship. “If sex is part of the agreement, and the person is no longer interested in sex, it affects the partner,” points out Wise.

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Symptoms of HSDD or FSIAD

A week—or even a month—of a reduced sex drive does not qualify as a disorder. “Sexual desire can wax and wane over the course of the menstrual period, over the course of a relationship, and over the course of our lives,” says Wise.

To be diagnosed, a person must meet several of the diagnostic criteria laid out in the DSM-5, explains Wise. These include a lack of interest in sexual activity, reduced (or absent) sexual thoughts and fantasies, and initiating sex less (or not at all), as well as being unreceptive when a partner initiates it.

A lack of desire or arousal when exposed to something erotic (like a romance novel, porn, or a steamy photo) is another factor, as is not feeling pleasure (or feeling less pleasure) during sex. Finally, the DSM notes that a reduced or absent genital—or non-genital—sensation during sexual encounters is a criteria for diagnosis.

Basically HSDD is a situation in which a woman really has no libido—she doesn’t think about sex, she doesn’t want sex, she doesn’t desire sex,” says Dr. Streicher. To be diagnosed, a woman must experience these symptoms for six months or more, and feel distress over it.

One caveat: The symptoms must not due to an underlying, fixable medical condition, says Dr. Streicher. For instance, if a woman avoids intercourse because it's painful, that's not a disorder. It's only HSDD if the pain is resolved, and the woman's libido remains low, she says.

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Treatment options for HSDD

Medications are available to treat HSDD.

There are two FDA-approved options: Addyi (flibanserin) modulates the neurotransmitters in the brain, resulting in more sexual thoughts, says Dr. Streicher. This drug is taken daily. The other option, Vyleesi (bremelanotide), is an on-demand injection—about 30 minutes after taking it, there’s an increase in dopamine, explains Dr. Streicher. The effectiveness rate of both medications is moderate, she says. Another safe, effective treatment option is off-label use of testosterone, says Dr. Streicher.

“None of these are miracle drugs,” says Dr. Streicher, who says it’s rare for her center to prescribe a drug without also suggesting sex therapy. “I think a pharmacologic approach, prescribing a drug, might give someone a nice kickstart, but it’s also critically important to have the element of sex therapy along with that,” she says.

Sex therapy can help uncover and address any underlying factors—such as high levels of stress, previous trauma, or relationship issues—that are contributing to a lowered libido. Wise works with patients to uncover what's going on in their lives that might be dampening their libido, and then provide them with tools and solutions that can help them regain desire. "The capacity to enjoy sex really is predicated with being in a relaxed, receptive state, and being attuned to our body," says Wise.

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How to get help

If your sex drive is in a slump, and you wish it wasn’t, start by talking to your doctor. Dr. Streicher recommends making a separate appointment with your gynecologist and not waiting for your annual—during which your doctor may be rushed. If your doctor does not seem knowledgeable or comfortable discussing the topic, try connecting with an AASECT-certified and trained sex therapist, suggests Dr. Streicher.

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