Diminished function of ovaries/testes with consequent lower levels of sex hormones.Encyclopedia Entry for Hypogonadism :Hypogonadism. The cause of hypogonadism can be primary or central (secondary). In primary hypogonadism, the ovaries or testes themselves do not function properly. Causes of primary hypogonadism include: Certain autoimmune disorders Genetic and developmental disorders Infection Liver and kidney disease Radiation Surgery Trauma The most common genetic disorders that cause primary hypogonadism are Turner syndrome (in women) and Klinefelter syndrome (in men). If you already have other autoimmune disorders you may be at higher risk of autoimmune damage to the gonads. These can include disorders that affect the liver, adrenal glands, and thyroid glands, as well as type 1 diabetes. In central hypogonadism, the centers in the brain that control the gonads (hypothalamus and pituitary) do not function properly. Causes of central hypogonadism include: Anorexia nervosa Bleeding in the area of the pituitary Taking medicines, such as glucocorticoids and opiates Stopping anabolic steriods Genetic problems Infections Nutritional deficiencies Iron excess ( hemochromatosis ) Radiation Rapid, significant weight loss (including weight loss after bariatric surgery) Surgery Trauma Tumors A genetic cause of central hypogonadism is Kallmann syndrome. Many people with this condition also have a decreased sense of smell.Girls who have hypogonadism will not begin menstruating. Hypogonadism can affect their breast development and height. If hypogonadism occurs after puberty, symptoms in women include: Hot flashes Energy and mood changes Menstruation stops In boys, hypogonadism affects muscle, beard, genital and voice development. It also leads to growth problems. In men the symptoms are: Breast enlargement Muscle loss Decreased interest in sex (low libido) If a pituitary or other brain tumor is present (central hypogonadism), there may be: Headaches or vision loss Milky breast discharge (from a prolactinoma) Symptoms of other hormonal deficiencies (such as hypothyroidism ) The most common tumors affecting the pituitary are craniopharyngioma in children and prolactinoma adenomas in adults.You may need to have tests to check: Estrogen level (women) Follicle stimulating hormone ( FSH level ) and luteinizing hormone ( LH) level Testosterone level (men) Other measures of pituitary function Other tests may include: Blood tests for anemia and iron Genetic tests including a karyotype to check chromosomal structure Prolactin level (milk hormone) Sperm count Thyroid tests Sometimes imaging tests are needed, such as a sonogram of the ovaries. If pituitary disease is suspected, an MRI or CT scan of the brain may be done.You may need to take hormone-based medicines. Estrogen and progesterone are used for girls and women. The medicines come in the form of a pill or skin patch. Testosterone is used for boys and men. The medicine can be given as a skin patch, skin gel, a solution applied to the armpit, a patch applied to the upper gum, or by injection. For women who have not had their uterus removed, combination treatment with estrogen and progesterone may decrease the chance of developing endometrial cancer. Women with hypogonadism who have low sex drive may also be prescribed low-dose testosterone or another male hormone called dehydroepiandrosterone (DHEA). In some women, injections or pills can be used to stimulate ovulation. Injections of pituitary hormone may be used to help men produce sperm. Other people may need surgery and radiation therapy if there is a pituitary or hypothalamic cause of the disorder.Many forms of hypogonadism are treatable and have a good outlook.In women, hypogonadism may cause infertility. Menopause is a form of hypogonadism that occurs naturally. It can cause hot flashes, vaginal dryness, and irritability as estrogen levels fall. The risk of osteoporosis and heart disease increase after menopause. Some women with hypogonadism take estrogen therapy , most often those who have early menopause. But long-term used of hormone therapy can increase the risk of breast cancer, blood clots and heart disease. Women should talk with their health care provider about the risks and benefits of hormone replacement therapy with your doctor. In men, hypogonadism results in loss of sex drive and may cause: Impotence Infertility Osteoporosis Weakness Men normally have lower testosterone as they age. However, the decline in hormone levels is not as dramatic as it is in women.Talk to your provider if you notice: Breast discharge Breast enlargement (men) Hot flashes (women) Impotence Loss of body hair Loss of menstrual period Problems getting pregnant Problems with your sex drive Weakness Both men and women should call their provider if they have headaches or vision problems.Maintaining fitness, normal body weight and healthy eating habits may help in some cases. Other causes may not be preventable.Gonadal deficiency; Testicular failure; Ovarian failure.Ali O, Donohoue PA. Hypofunction of the testes