Several reports indicate that raised serum prolactin concentrations occur in 15 to 20 per cent of women with amenorrhea1 , 2 and that when the prolactin levels are reduced, normal ovulation cycles and fertility return.3 , 4 Successful management of these cases depends on reliable identification of hyperprolactinemic amenorrhea and accurate diagnosis of its causes. Clinical discrimination will be needed, however, if endocrine laboratories are not to be overwhelmed by requests for prolactin assays. What, then, are the clinical features that should prompt a request for prolactin measurements in women with amenorrhea? First of all, though galactorrhea on its own is rarely associated with . . .