[Functional hypothalamic amenorrheas. II. Clinical aspects].
The most important causes of the functional hypothalamic amenorrhea (FHA), that are psychological stress, physical stress and weight loss, are associated with a decrease of the frequency of the LH secretory pulses and with a state of hypercortisolism. The slowing down of the LH pulse frequency is difficult to demonstrate in clinical practice. The classical symptoms of FHA which are low gonadotropin levels, and hypogonadism are not very specific. The diagnosis of FHA is therefore one of exclusion. Recent physiopathological studies have individualised new symptoms that are hypercortisolism, hypoprolactinaemia and an important increase in the night serum levels of melatonine, all of which could help to confirm the diagnosis. FHA is relatively frequent and its treatment with pulsatile GnRH administration or naltrexone is very successful.