Thursday, October 28, 2010

Is women’s sexual dysfunction due to testosterone deficiency?

Sexual dysfunction or decreased libido is a common complaint in women. While the exact numbers are not known, it is estimated that decreased libido in women affects close to 3-13 percent of women of all ages. For many years, it has been believed that the sexual dysfunction may be due to a deficiency in the male sex hormone, testosterone.   

Androgen activity has long been thought to be a major modulator of a woman’s sexual desire and response. Many women have been self-treating themselves with off- label prescriptions of testosterone. Some have even been using formulations that are especially designed to treat men with hypogonadism.

Many studies have looked at levels of testosterone in women who have a variety of sexual disorders but the results have been inconsistent and not always reproducible. A few randomized studies have shown that there is only a mild benefit from use of transdermal testosterone in postmenopausal women who have low sexual desire. Based on these studies, topical testosterone is approved for use in many European countries. 

However, in the USA, such therapy has been viewed with suspicion chiefly because the long-term side effects are not known. The other reason why testosterone therapy has not been widely used in the USA is that testosterone deficiency has never convincingly been demonstrated in women with low sexual desire.

The problem with measurement of testosterone is that it has several metabolites and most are difficult to measure in blood or urine. The one major criticism of the studies that showed benefit of testosterone is that not all women responded and the benefits were mild. In addition, some women did engage sexually but did not achieve any satisfaction.

In conclusion, more than 3 million prescriptions for non-compounded testosterone formulation are written each year. However, women who resort to these hormones should first understand that no androgen deficiency has ever been shown in sexually dysfunctional people. Moreover, the long-term side effects of this male sex hormone are not trivial. Finally, Testosterone therapy is extremely risky in women who have a history of breast or uterine cancer or those who have heart or liver disease.