Influence of pregnancies on prolactinomas.

Hyperprolactinaemic patients desiring pregnancy with a normal sella turcica or radiological evidence for a microprolactinoma without suprasellar extension were treated with bromocriptine. Females desiring pregnancy with large adenomas or suprasellar extension were treated by transsphenoidal surgery and in most instances post-operatively with bromocriptine. This differentiated management allowed the outcome of 65 pregnancies with delivery at term without complications related to the sella turcica. Considerable variations of prolactin levels during pregnancy suggesting different oestrogen sensitivity of the prolactinoma cells were encountered. However, a rapid fall of the prolactin levels in 60 patients after termination of pregnancy indicated that oestrogen stimulation does not cause persisting growth of the adenoma. In contrast, in 10% of pregnancies of hyperprolactinaemic patients a reduction of the prolactin levels has been observed leading to spontaneous ovulatory cycles in 5 patients.