Ann Endocrinol (Paris). 2007 Jun;68(2-3):106-12. "In women with microadenomas, pregnancy generally has little impact on their adenoma, delivery is normal and breast-feeding is allowed."
Pregnancy and breast-feeding are times when prolactin levels are VERY high, in the upper double digit range and up to 600 ng/ml during pregnancy. Estrogen levels are also very high during pregnancy (especially mid and late), way above what we could ever experience.
"While the literature has little to say on this subject and provides no adverse information, professional experience suggests that this attitude should be amended and that women presenting microprolactinoma should be allowed to use current contraceptive pills"
J Clin Endocrinol Metab. 2007 Aug;92(
:2861-5."observational studies have shown that pregnancy has a favorable effect on the natural history of preexisting prolactinomas. Prolactin levels are lower after delivery than before conception and complete remission of hyperprolactinemia has been reported in 17–37% of women after pregnancy (19, 20). Changes in tumor vasculature resulting in pituitary necrosis, microinfarction, or hemorrhage have been suggested as potential mechanisms to explain how pregnancy might lead to normalization of prolactin (21)."
Growth Horm IGF Res. 2003 Aug;13 Suppl A:S38-44."A review summarized results of 16 series reported between 1979 and 1985 totaling 246 women with microadenomas and 91 women with macroadenomas who became pregnant [17]. Subsequently, three series totaling an additional 117 women with microadenomas and 60 women with macroadenomas have been reported [18], [19] and [20]. When these data are combined [17], [18], [19] and [20], only 5 of the 363 women (1.4%) with microadenomas had symptoms of tumor enlargement (headaches or visual disturbances or both) (Table 1). In no case was surgical intervention necessary."
in ciswomen, pregnancy is rarely (1-5 % of time) associated with symptoms that would suggest an enlargement of an already existing prolactinoma when the prolactinoma is small and this frequency of enlargement is estimated to not be different from what it would be, in the absence of pregnancy. Hence, the risk is negligible. This number, however, significantly increases to 20-40% when the prolactinoma is large. No studies have shown that pregnancy can cause a prolactinoma.
No prolactinoma has ever been observed in transsexual women taking only bio-identical estradiol and bio-identical progesterone. Most commonly, the use of cyproterone acetate has been associated with prolactinoma, other progestins and non bio-identical estrogen.
