Pre-pregnancy overweight and weight gain during pregnancy increase the risk of gestational anemia

Abstract Objective: To study the double burden of overweight and anemia in Mexican women during pregnancy and if pre-pregnancy body mass index (BMI) and weight gain are associated with the development of anemia. Methods: In a sample of 98 pregnant women from an ongoing birth cohort, weight and hemoglobin at different gestational weeks, as well as pre-pregnancy BMI (self-reported) were obtained. An adjusted logistic model for longitudinal data was used to estimate the probability of presenting anemia according to pre-pregnancy overweight status (BMI > 25kg/m 2 ) and weight gain, including an interaction term between these two variables. Results: At the end of pregnancy the combined prevalence of overweight and anemia was 18%. The probability of developing anemia was different from zero among overweight women at the beginning of pregnancy and weight gain > 6.5kg kg (up to 8%, p <0.05); furthermore, the prevalence was higher than zero in those women with a normal pre-pregnancy BMI (<25kg/m 2 ) and a weight gain < 12 Kg (up to 9%, p <0.05). Conclusion: anemia increases with the combinations of low weight gain in women with a normal pre-pregnancy BMI as well as excessive weight gain in women with pre-pregnancy overweight.