BRD2 and polycystic ovary syndrome: The serum concentration of basal E2 and basal FSH were lower in the PCOS group than in the non-PCOS group (basal E2: 39.51 ± 51.17 vs. 60.08 ± 62.69, P<0.001; basal FSH: 5.07 ± 1.41 vs. 6.02 ± 3.78, P<0.001).