PRL and diabetes insipidus: Our analysis showed odds ratio of postoperative biochemical remission in males vs. females of 0.83 (95% CI 0.59–1.15, P = 0.26), odds ratio of gross total resection in male vs. female patients of 0.68 (95% CI 0.34–1.39, P = 0.30), odds ratio of postoperative diabetes insipidus in male vs. female patients of 0.40 (95% CI 0.26–0.64, P < 0.0001), and a mean difference of preoperative level of prolactin in male vs. female patients of 11.62 (95% CI − 119.04–142.27, P = 0.86).