Estrogens are important in maintaining the condition of the vaginal lining and its elasticity, and in producing vaginal lubrication. They also help preserve the texture and function of a woman's breasts. In men, estrogens have no known function. An unusually high level, however, may reduce sexual appetite, cause erectile difficulties, produce some breast enlargement, and result in the loss of body hair in some men. Androgens are sex hormones produced primarily by a male's testes, but are also produced in small amounts by the female's ovaries and the adrenal gland, an organ found in both sexes.
Androgens help trigger the development of the testes and penis in the male fetus.
They jump start the process of puberty and influence the development of facial, body and pubic hair, deepening of the voice, and muscle development, the male secondary sex characteristics. After puberty, androgens, specifically testosterone, play a role in the regulation of the sex drive. Large deficiencies of testosterone may cause a drop in sexual desire, and excessive testosterone may heighten sexual interest in both sexes. However, testosterone levels are poorly correlated with sexual interest and drive when they are within the average range. In men, too little testosterone may cause difficulty obtaining or maintaining erections, but it is not clear whether testosterone deficiencies interfere with female sexual functioning apart from reducing desire.