Outcome of prolactinoma after pregnancy and lactation: a study on 73 patients.

CONTEXT

Prolactinoma is the most frequent pituitary tumour among women of child-bearing age. Only a few studies have addressed the outcome of prolactinoma after pregnancy.

OBJECTIVE

To study remission, defined as prolactin normalization without medical treatment, after pregnancy and lactation in women with prolactinoma.

PATIENTS AND METHODS

A retrospective study conducted in 2 Belgian academic centres including 73 patients (54 microprolactinomas and 19 macroprolactinomas) with 104 pregnancies continuing beyond first trimester. Dopamine agonists were stopped in early pregnancy in all treated cases. Prolactin level and adenoma size at pituitary magnetic resonance imaging (MRI) were recorded before pregnancy and throughout follow-up.

RESULTS

Thirty of 73 women (41%) were in remission after a median follow-up of 22 months after delivery or cessation of lactation. Adenoma size at diagnosis was smaller in women in remission (5 vs 8 mm). There was a nonsignificant higher rate of remission for microprolactinomas than for macroprolactinoma (46% vs 26%). The first pituitary MRI after pregnancy and lactation showed no tumour and a decreased adenoma size in 23% and 39% of women, respectively. MRI normalization was associated with remission. The number of pregnancies per woman as well as breastfeeding and its duration did not influence remission rate.

CONCLUSION

More than 40% of women with previous diagnosis of prolactinoma have normal PRL level without medical treatment for a median follow-up of 22 months after pregnancy and lactation. The likelihood of remission is associated with a smaller initial adenoma size and normalization of pituitary MRI after pregnancy.