GSTM1 and anemia (phenotype): According to the World Health Organization (WHO), anemia is defined as hemoglobin (Hb) <120 g/L in non-pregnant women and <110 g/L in pregnant women, with severity classified as mild (11.0-11.9 g/dL), moderate (8.0-10.9 g/dL), and severe (<8.0 g/dL) [3].