Gonadal Sex Hormones

Gonadal sex hormones are produced by gonadotropins (FSH- Follicle Stimulating Hormone and LH- Luteinizing hormone) from the anterior pituitary gland located at the base of the brain. They stimulate male and female gonads to produce hormones of their own. FSH and LH secretion is controlled by GnRH (gonadotropin-releasing hormone), which is a releasing hormone from the hypothalamus. The sex of an embryo is determined at fertilization, but secondary sex characteristics develop at puberty. Testosterone regulation is important because males need just enough to develop increased muscle and bone mass, growth of body hair, and the healthy development of reproductive tissues in the testes and prostate. Women produce a small amount of testosterone but a more essential hormone is estrogen, which is produced by developing follicles in the ovaries. FSH stimulates estrogen production in the ovaries. Estrogen is responsible for breast development, thickening of the endometrium, and the menstrual cycle. All of the gonadal sex hormones are important in keeping the body’s sexual characteristics at a normal level and also contribute to overall development. * * A disease of the malfunction of the testes is hypogonadism, a disorder where the testes do not produce enough testosterone. Primary hypogonadism is when there is an abnormality with the testicles only, but secondary hypogonadism is when there is a problem with the pituitary gland, inhibiting chemical messages for testosterone production. Hypogonadism may result in erectile dysfunction, infertility, decreased size or firmness of testes, sex drive, muscle mass, and facial hair. Hypogonadism may be caused by many disorders including but not limited to cancer, undescended testes, Kleinfelter’s syndrome, testicular trauma, pituitary disorders, and medication. *