How does pregnancy affect the patients with pituitary adenomas: a study on 113 pregnancies from Turkey

Data regarding pregnancies in relation to pituitary tumors are limited. The effects of pregnancy on pituitary adenomas and the effects of adenoma itself (hormonal activity, mass effects and pituitary insufficiency) and/or treatment on the ongoing gestation and developing fetus were evaluated.

The study was a retrospective study. A questionnaire involving questions regarding medical history before index gestation, history of related pregnancy, result of index gestation and postpartum follow-up of the patients was filled by the investigator in one of the eight Referral Endocrinology Centers from Turkey.

One hundred and thirteen (83 prolactinoma, 21 acromegaly, 8 NFPA and 1 plurihormonal pituitary adenoma) pregnancies of 87 (60 prolactinoma, 19 acromegaly, 7 NFPA and 1 plurihormonal pituitary adenoma) patients were reviewed. The clinically important pregnancy-related tumor growth of pituitary adenomas was found to be low in previously treated adenomas. Prolactinomas were more likely to increase in size during pregnancy especially if effective prior treatment was lacking. The risk of hypopituitarism is also minimal due to pituitary adenomas during pregnancy. The results of pregnancies did not differ in patients who were on medical treatment or not for prolactinomas and acromegaly during gestation. Neural tube defect and microcephaly associated with maternal cabergoline use; Down syndrome and corpus callosum agenesis associated with maternal bromocriptine use; unilateral congenital cataract, craniosynostosis and microcephaly associated with maternal acromegaly were detected for the first time.

Medical treatment can be safely done stopped in patients with prolactinoma and acromegaly when pregnancy is confirmed and reinstituted when necessary. Prospective studies may help to determine the effects of medical treatment during gestation on the mother and fetus.