A total of 61.5% (n = 1164) of women were anaemic (Hb ≤100 g/L, as per PNG guidelines [37]): 32.7% (n = 618) had mild anaemia (Hb > 90 and ≤ 100 g/L), 24.7% (468) had moderate anaemia (Hb >70 and ≤90 g/L), and 4.1% (78) had severe anaemia (Hb ≤70 g/L). This evidence concerns the gene GSTM1 and anemia (phenotype).