GSTM1 and anemia (phenotype): Taking into account all the multiple underlying factors of anaemia in the tests of associations on Hb levels, it was malaria tablet given at antenatal clinic (p = 0.035), MUAC (p = 0.043), ZPP (p<0.001), ZPP/Hb ratio (p<0.001) and body iron stores (p<0.001) that had a significant effect on the Hb levels.