GSTM1 and Infertility: A significantly higher level (p≤0.001; independent sample t-test) of AChE enzyme activity was found in the infertile group (0.64±0.26 mU/μmol Hb, 95% CI 0.56–0.72; n = 42) as compared to non-infertile cohort (0.29±0.28 mU/μmol Hb, 95% CI 0.21–0.36; n = 50).