Content written by Irwin Goldstein, MD

Thyroid hormones, similar to estrogen, progesterone and testosterone hormones, act on cells to direct the synthesis and release of various proteins. These hormone-mediated proteins are responsible for structure and function of many tissues, including genital tissues. Female genital tissues, similar to other tissues in the body, depend upon thyroid hormone for regulation of cell metabolism. For example, thyroid hormone acts on clitoral and vaginal smooth muscle cells to improve the responsiveness of the smooth muscle. The tone of the smooth muscle in the clitoris and vagina determines the state of sexual arousal. Clitoral and vaginal smooth muscle cells relax during sexual arousal to allow for blood to engorge the tissues. The health of the smooth muscles cells is, in part, determined by the action of the thyroid hormone.

Hypothyroidism is a condition caused by having too little thyroid hormone act on the body’s tissues. Hypothyroidism is a condition that affects over five million Americans, in which the body lacks sufficient thyroid hormone. It is estimated that as many as 10% of American women may have some degree of thyroid hormone deficiency. Millions of women with sexual health problems are currently hypothyroid and don’t know they have thyroid problems. Hypothyroid symptoms are non-specific and may include fatigue?and weakness,?weight gain or increased difficulty losing weight, coarse, dry hair and dry, rough pale skin, hair loss, intolerance to cold and inability to tolerate the cold like those around you, muscle cramps and frequent muscle aches, constipation, depression, irritability, memory loss, abnormal menstrual cycles, and sexual dysfunction.

In one study, the levels of sexual function of 30 women with hypothyroidsm were compared to the data of a control group of healthy age-matched women. As a group, those women with thyroid disorders had significantly worse lubrication and orgasm and significantly more sexual pain compared with the control group. In summary, some patients with hypothyroid hormone disorders experience sexual dysfunctions that may be reversed by normalizing thyroid hormone levels.