Testosterone is an androgen steroid hormone that is usually linked to male sexuality. It stimulates the growth of normal male sexual organs, leads to deepening of the male voice, stimulates facial and pubic hair growth, and is essential in the sexual behavior of men. Testosterone is made not only in the testes of men but also in the ovaries of women and in the adrenal glands of both men and women. Abnormally high testosterone levels in women can lead to a variety of symptoms. Most often, women with high testosterone levels develop male pattern hair growth (hirsutism), especially on their faces and chests. More rarely, over time some women may experience virilization, which is increased muscle mass, redistribution of body fat, enlargement of the clitoris, deepening of the voice, male pattern baldness, acne, and increased perspiration. It is important to note that some women develop hirsutism without having a high testosterone level.

Increased testosterone levels in women are most often caused by polycystic ovaries. Less commonly, when testosterone levels are very elevated, ovarian cancer is a concern. Adrenal gland problems may contribute as well.