PRL and endometriosis: In their study, Lima et al. included 18 infertile women with endometriosis stage I/II, 10 infertile women with stage III/IV, and 21 fertile women without endometriosis undergoing laparoscopy for tubal sterilisation and reported that the basal prolactin serum levels in patients with endometriosis stage III–IV and in patients with endometriosis stage I–II were higher (28.9 ± 2.1 ng/mL and 23.4 ± 3.7 ng/mL) when compared to the basal prolactin serum levels in fertile patients without endometriosis (13.2 ± 2.1 ng/mL).