The prevalence of anemia (Hb <11.0 g/dL) was 37%, 63%, 58%; ID (Ft <15 μg/L) was 16%, 20%, 38%; ID (TIBC ≥ 400 μg/L) was 19%, 29% and 40%; ID (TSAT <16%) was 12%, 9% and 17%; iron deficiency anemia (IDA) based on Ft <15 μg/L and Hb <11.0 g/dL was 6%, 12% and 25% for 1st, 2nd and 3rd trimesters, respectively (Table 2). This evidence concerns the gene GSTM1 and anemia (phenotype).