Purpose: Approximately 0.6% of the adult population identifies as transgender. Gender affirming hormone treatment (GAHT) is required by many to develop physical and psychological characteristics that align with their gender identity. Once started, GAHT is continued lifelong and at higher doses than conventionally used in the management of cis-gendered women. Hyperprolactinemia and pituitary lactotroph adenomas are a potential consequence of GAHT.
Methods: Case series of three transfeminine women with hyperprolactinemia during gender affirming hormone treatment.
Results: We report two new cases of prolactinoma and one new case of marked hyperprolactinemia without pituitary adenoma associated with GAHT in transwomen at different stages of hormonal transition. Novel aspects of our case series include the first report of a prolactinoma in a transwoman associated with spironolactone and the alternate progestin medroxyprogesterone acetate and documentation of the transient changes in prolactin from baseline (prior to feminizing hormones) in two transwomen which demonstrate that marked hyperprolactinemia develops early in the course of GAHT.
Conclusions: Transgender women receiving GAHT may be at increased risk for prolactinoma. As the number of transwomen seeking GAHT continues to increase, hyperprolactinemia and GAHT-associated prolactinoma may become an increasingly important component of endocrine practice. Screening of prolactin levels in transwomen receiving GAHT could potentially prevent morbidity related to hyperprolactinemia and allow for early detection of prolactin secreting pituitary adenomas.
Keywords: Cyproterone acetate; Gender affirming hormone therapy; Hyperprolactinemia; Pituitary adenoma; Prolactinoma; Transgender.