GSTM1 and malaria: The mean difference (95% CI) in Hb between the AZI-SP and the control group was 2 g/l (0–4, P = 0.017; global P = 0.058) at 28.00–33.99 gw in the main analysis, adjusted for the timing of measurement and Hb at enrollment, and 2 g/l (1–4, P = 0.011; global P = 0.040) in the analysis additionally adjusted for malaria, gravidity, and adolescence at enrollment (Table 3).