Pituitary tumors have profound effects on fertility, whereas pregnancy affe
cts both the behavior of pituitary tumors and their management. Tumors may
impair fertility by hormonal hypersecretion, when functional, or by destruc
tion of pituitary hormone-secreting cells. Prolactin hypersecretion inhibit
s the hypothalamic-pituitary gonadotropic axis, leading to anovulation, adr
enocorticotropic hormone (ACTH) and growth hormone (GH)-secreting tumors ca
use infertility due to excess adrenal androgen production. The normal pitui
tary and frequently, pituitary tumors, increase in size during pregnancy an
d together may cause headaches and impaired vision due to mass effects. For
prolactinomas, the risk with microadenomas is very low, although with macr
oadenomas, may be as high as 36%, warranting consideration of therapy befor
e pregnancy. Prolactinomas frequently respond to dopamine agonists. The lar
gest experience has been with bromocriptine, which is considered not to hav
e untoward effects on the fetus; less experience exists for cabergoline, al
though no safety issues have been raised. Spontaneous tumor regression/remi
ssion of prolactinomas may occur after delivery, particularly in those tumo
rs first detected during pregnancy. Somatotropinomas may also exhibit sympt
omatic enlargement during pregnancy. They usually respond to octreotide, al
though the drug's tumor-suppressive activity is less than that of bromocrip
tine and experience with this drug in pregnancy is limited. ACTH-secreting
tumors cause an increase in maternal and fetal morbidity and mortality. Sur
gical therapy is required, because pharmacotherapy exhibits unacceptable to
xicity. Treatment of thyroid-stimulating hormone (TSH)-secreting and of non
functioning tumors is by surgery.