Hypogonadism (a condition where the gonads – testes for men and ovaries for women – have diminished activity) can decrease estrogen. In primary hypogonadism, elevated serum gonadotropins are detected on at least two occasions several weeks apart, indicating gonadal failure. In secondary hypogonadism (where the cause is hypothalamic or pituitary dysfunction) serum levels of gonadotropins may be low.
