Women not being “in the mood” has been snarky comedy gold since Shakespeare's day and probably earlier. But although it's a real problem – the clinical term is “hypoactive sexual disorder” – its nature is all relative. There is no magic number or metric that defines “low sex drive.” Your sex drive is “low” only if it presents a problem to you or your partner.

The fact of the matter is that a woman's sex drive is going to be all over the place during her life. The start (and ending) of relationships, pregnancy, illness, menopause and any life changes can have direct and significant effect upon her ability to get in the mood.

This all said, these are the symptoms of a low sex drive:

• No interest in any type of sexual activity, including self-stimulation
• No, or only very occasional, sexual fantasies or thoughts
• Concern over lack of sexual activity or fantasies

The causes of hypoactive sexual disorder may be mental or physical.

Psychological causes include anxiety, depression, poor body image, low self-esteem, or a history of sexual abuse. Because women often count an emotional closeness as a key ingredient for intimacy, any kind of problem in the relationship – infidelity, fights, unresolved conflicts, etc. – may result inhypoactive sexual disorder.

Physical causes for a woman's low sex drive are numerous, and include diseases such as arthritis, high blood pressure, cancer, diabetes, coronary artery diseases and a number of neurological ailments. Any kind of surgery, but especially to the breasts or the genital tract, can diminish sex drive.

Lifestyle plays a big role in hypoactive sexual disorder. If a woman is chronically fatigued because of her work and/or childcare responsibilities, it can have an effect in the bedroom. Alcohol and drug use can greatly diminish a woman's sex drive, and the diminishedblood flow resulting from smoking can have the same effect.

If you think your sex drive is lower than you want it to be, see your doctor. (Whether or not your doctor “officially” diagnoses you with hypoactive sexual disorder, she is still in a position to help.) She may perform a pelvic exam to check for physical problems that could contribute to the condition, such as vaginal dryness or the thinning of your genital tissues. Your doctor may also order blood tests to check hormone levels and look for evidence of thyroid problems, diabetes, high cholesterol and liver disorders. Your doctor can also analyze the meds your are taking and determine whether these are contributing to your condition.

In addition to psychological counseling, there are other, more tangible, approaches your doctor may take. Hormone therapy, in the form of estrogen delivered throughout your body via a pill, spray, gel or patch can have a positive effect on mood and brain function related to sexual desire.

Your doctor might prescribe the antidepressant Flibanserin. This is a daily pill which the Food and Drug Administration has approved for use by pre-menopausal women with a low sex drive.