When additionally adjusted for blood pressure at mid-pregnancy, (Model 3) participants with anaemia (Hb < 10.5 g/dL) still tended to have 2.85 times higher odds for pregnancy-induced prehypertension than women without anaemia (OR: 2.85, 95% CI: 1.00, 8.10). This evidence concerns the gene GSTM1 and anemia (phenotype).