Hypogonadotropic hypogonadism

Hypogonadotropic hypogonadism (HH), is a disorder where the pituitary gland fails to produce the required levels of the hormones (LH and/or FSH) which are needed to stimulate the gonads (testicles or ovaries) to function normally. This usually means that the gonads produce unusually low levels of sex hormones (testosterone, progesterone, or estrogen), but it can also lead to other functional problems such as insufficient sperm in male HH. It may be caused by problems with either the hypothalamus or pituitary gland, in either case leading to abnormal functioning of the hypothalamic-pituitary-gonadal axis (HPG axis).

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