Evaluation of serum prolactin levels in patients with endometriosis and infertility

The aim of this study was to clarify the significance of serum prolactin co ncentrations in patients with infertility and endometriosis. Forty patients with infertility and laparoscopically proven endometriosis were recruited into the study. Basal serum prolactin levels and prolactin levels after TRH administration were measured. The mean basal serum prolactin concentration s were 12.5, 16.5, 19.5, and 26.5 ng/ml and those after thyrotropin-releasi ng hormone (TRH) administration were 88.3, 114.2, 125.3 and 138.8 ng/ml in patients with stages I, II, III and IV endometriosis, respectively. A stati stically significant relationship was found between the basal serum prolact in levels as well as those after TRH injection and the stage of the endomet riosis. The patients were divided in two groups. Group I consisted of 20 pa tients who did not receive any treatment, while group II consisted of 20 pa tients who were initially treated with GnRH analogues for 24 week and subse quently with several therapeutic schemes in order to improve their fecundit y. The pregnancy rate was not different between the two groups. The patient s, however, who did not become pregnant had higher serum prolactin concentr ations after TRH administration as compared to those who conceived. We conc lude that occult hyperprolactinemia may be a cause of infertility in patien ts with endometriosis.