[Hyperprolactinemia]

In clinical endocrinology an elevated prolactin concentration in serum is often encountered. This may be either physiological during pregnancy and lactation or pathological in all other cases. The most frequent causes are drugs (dopamine antagonists, estrogens) and primary hypothyroidism. These hyperprolactinemic states have to be distinguished from prolactinomas and other tumors of the pituitary gland, which can increase the level of prolactin in the serum through different mechanisms. Drug therapy with dopamine agonists will almost always decrease prolactin levels, but will rarely cure the disease. Long-term success rates after surgery are 50% for microadenomas and 10 to 15% for macroadenomas. Therefore, the decision to operate should be made after careful discussion between the surgeon and the endocrinologist. Pregnancy will rarely cause expansion of the tumors, more often with macro- than with microadenomas. Pregnant women with prolactinomas have to be followed clinically, and drug therapy has to be instituted immediately when clinical signs of tumor progression exist.