Prolactinomas and Pregnancy

Abstract

Prolactinomas are the most frequent pituitary tumors. Treatment of infertility in such tumors usually is very successful. On the other hand, reports of pituitary tumor growth during pregnancy have been described since bromocriptine started to be used. Since then, dopamine agonists (DA) have been increasingly used as the first-choice treatment of prolactinomas, with surgery being reserved for resistance or persistent intolerance to DA or for special situations. More recently other DA, such as quinagolide and cabergoline have shown better tolerance than bromocriptine with similar or greater efficacy. Cabergoline is now the first choice drug but its use in pregnancy is still under evaluation. We followed 71 term pregnancies in women bearing microprolactinomas. Of the 22 patients with previous surgery, none presented symptoms of tumor growth. Of the 41 pregnant patients treated with bromocriptine alone, only one (2.4%) presented with headaches, which regressed with drug reintroduction. Fifty one term pregnancies in patients with macroprolactinomas were followed by us. Of those, 21 were in patients with previous surgery and none of them presented clinical evidence of tumor growth. On the other hand, of the 30 patients treated only with pre-gestational bromocriptine, 11 (37%) manifested complaints related to tumor growth. A non-hormonal contraceptive should be the use along with a DA drug until tumor shrinkage within sellar boundaries has been evidenced. After pregnancy has been confirmed, the DA can be withdrawn and the patient must be closely followed. If tumor expansion is suspected, confirmation can be made through MRI and by visual field testing. Reintroduction of bromocriptine in such cases can lead to tumor reduction and clinical improvement. Surgery can also be employed as treatment for symptomatic tumor growth in pregnancy.