An observational study of pregnancy and post-partum outcomes in women with prolactinoma treated with dopamine agonists

Background In women with prolactinoma medical treatment with dopamine agonists (DA) can restore fertility. A number of studies have established the safety of DA during pregnancy and the impact of pregnancy and lactation on remission of prolactinoma. However, the total number of reported cases remains modest and further evidence is needed. Aims To evaluate the safety of DA during pregnancy and remission of prolactinoma after pregnancy and lactation. Materials and Methods Retrospective cohort study (2002-2014) of 57 pregnancies in 47 women with prolactinoma who received DA. Neonatal and pregnancy complications were recorded. Prolactin levels and treatment data were collected at the time of diagnosis, pre-conception, during pregnancy and lactation, and post-partum (up to 114 months). Results DA treatment was stopped a median of 4.5 weeks after conception in 49 pregnancies (86%). There were 49 live births (86% of pregnancies) and six miscarriages. Six pregnancies had an adverse neonatal outcome including two with congenital malformations. Following 26% of pregnancies women achieved remission after birth or lactation, and 25% of women were in remission at last follow-up. Remission was associated with older maternal age (P = 0.036), a lower prolactin level at diagnosis (P = 0.037), and a smaller adenoma at diagnosis (P = 0.045). Conclusions Successful pregnancy and lactation is common after DA treatment for prolactinoma. Fetal exposure in the first four weeks of pregnancy appears to be generally safe. Encouragingly, post-partum and after lactation a quarter of women had a normal prolactin level without medical treatment.