INS and endometriosis: After adjusting for potential confounders, number of previous pregnancies [adjusted odds ratio (aOR) 0.51, 95% confidence interval (CI) 0.43–0.62; P < 0.001], serum CA125 (aOR 1.02, 95% CI 1.01–1.03; P < 0.001), serum Glu (aOR 0.74, 95% CI 0.56–0.97; P = 0.027) and serum INS (aOR 1.03, 95% CI 1.01–1.04; P = 0.002) were found to be significantly associated with presence of endometriosis (Table 3).