Methylation levels (β-value) in the promoter regions of the leptin (LEP) (a), antimüllerian hormone (AMH) (b) and androgen receptor (AR) genes (c) in sons of control (control, n = 12), PCOS women (PCOS, n = 6) and PCOS women treated with metformin during pregnancy (PCOS+M, n = 6). Data are shown as median ± SEM. Dots indicate the cases in each group. Differences were calculated by one-way ANOVA followed by Bonferroni test or Kruskal-Wallis test followed by Dunn test. aP < 0.05 between control and PCOS; bP < 0.05 between control and PCOS+M; cP < 0.05 between PCOS and PCOS+M