The inclusion criteria for this study were as follows: (1) all study designs that reported data on anemia prevalence, risk factors, or neonatal and maternal outcomes, specifically in pregnant women; (2) anemia defined as a blood hemoglobin (Hb) concentration below 11 g/dl or a hematocrit level less than 33% per the WHO [4]; (3) only studies conducted in Egypt were considered; and (4) studies published between January 1, 2010, and August 18, 2024, were included. This evidence concerns the gene GSTM1 and anemia (phenotype).