The study encompassed 62 children aged 4-15 years: 51 with a confirmed diagnosis of celiac disease and 11 suspected of having celiac disease (during diagnostic studies). The control group included 30 healthy children aged 4-15 years. Serum prolactin concentration was measured using radioimmunoassay (RIA) kits. Serum prolactin concentrations were significantly higher in children with celiac disease not following a gluten-free diet than in the control group. Children with serious mucosal lesions revealed by small bowel mucosal biopsies had the highest serum prolactin concentrations. Of these children, 36% gad values higher than 15 ng/ml. Differences between children with celiac disease complying with a gluten-free diet and the control group were not significant.