GSTM1 and anemia (phenotype): We used data from an ongoing Maternal and Newborn Health Registry (MNHR) based in rural areas of Nagpur, Maharashtra, India, to: (1) describe the prevalence and trends of maternal anaemia and low BMI from 2009 to 2016; (2) describe the maternal demographic characteristics associated with different levels of maternal Hb and BMI from 2009 to 2016; (3) evaluate whether low BMI and anaemia were independent or synergistic risk factors for adverse pregnancy outcomes between 2009 and 2016; and (4) investigate whether low BMI and anaemia had additive or synergistic effects on poor birth outcomes.