Management of hyperprolactinemic infertility

Pathological hyperprolactinemia may cause defective ovulation and reduced fecundability. Abnormal prolactin (PRL) secretion is usually related to an idiopathic hypothalamic dysfunction or to the presence of a pituitary adenoma. The use of medication is the most common cause of functional hyperprolactinemia. Pituitary prolactin secreting adenoma is classified according to size: micro (the vast majority) being smaller than 10 mm in diameter or macroprolactinoma (very few) of larger size. An excessive PRL secretion decreases the pulsatile release of GnRH impairing the pituitary production of FSH and LH. Furthermore it may directly impair the endocrine activity of ovarian follicles. As a consequence: defective luteal phase, inconstant ovulation and chronic anovulation are conditions frequently observed in young hyperprolactinemic patients. In addition 5% of unselected, asymptomatic infertile women show hyperprolactinemia. In such patients fertility may be promoted with long-term use of dopaminergic drugs. The normalized PRL level induced by the treatment allows the occurrence of spontaneous ovulatory cycles or the normalization of the defective luteal phase. Treatment should be continued for at least one year since half of the pregnancies occurring during dopaminergic therapy start after the first 6 months of drug assumption. An ovarian stimulation with gonadotropin and the pulsatile administration of GnRH may also induce ovulatory cycles and fertility in the infertile hyperprolactinemic patients. Hyperprolactinemia either, due to hypothalamic dysfunction, as well as the presence of PRL secreting adenoma usually improves after delivery