Prevalence of anemia (Hb <11.0 g/dL) was 37%, 63%, 58%; ID (Ft <15 μg/L) was 16%, 20%, 38%; and iron deficiency anemia (IDA; based on low Ft and Hb) was 6%, 12%, 25% in 1st, 2nd and 3rd trimesters, respectively. The gene discussed is GSTM1; the disease is anemia (phenotype).