Long-Term Association Between Maternal Preconception Hemoglobin Concentration, Anemia, and Child Health and Development in Vietnam

Background: The long-term association between preconception maternal hemoglobin (Hb) concentrations and child health and develop-ment is unclear.Objectives: We examined associations between maternal preconception Hb concentrations and anemia with 1) birth outcomes (weight, length, preterm, gestational age, small for gestational age); 2) child Hb at 3 mo, 6 mo, 12 mo, and 24 mo; and 3) motor and mental development at 12 mo and 24 mo (Bayley scales for infant development) and cognitive functioning at 6-7 y (Wechsler Intelligence Scale for Children).Methods: We used data from a randomized controlled trial (PRECONCEPT) conducted in Vietnam. Over 5000 women who were intending to conceive were recruited, and offspring were prospectively followed from birth (n = 1599) through 6-7 y (n = 1318). Multivariable linear and logistic regressions were used to assess the association between preconception Hb or anemia (Hb < 12g/dL) on child health and development outcomes, adjusted by supplementation group (tested for interactions) and confounding at maternal, child, and household levels.Results: At preconception enrollment, 20% of the women were anemic. Maternal preconception Hb was positively associated with child Hb at 3 mo (0.06; 95% CI: 0.01, 0.12), 6 mo (0.08; 95% CI: 0.03, 0.13), 12 mo (0.10; 95% CI: 0.04, 0.15), and 24 mo (0.07; 95% CI: 0.02, 0.12). Likewise, maternal preconception Hb was associated with reduced risk of child anemia at 6 mo (0.89; 95% CI: 0.81, 0.98), 12 mo (0.81; 95% CI: 0.74, 0.89), and 24 mo (0.87; 95% CI: 0.79, 0.95). Maternal preconception anemia was negatively associated with cognition (-1.64; 95% CI: -3.09, -0.19) and language development (-1.61; 95% CI: -3.20, -0.03) at 24 mo. Preconception Hb was not associated with birth outcomes or cognitive outcomes at 6-7 y. Conclusions: Maternal preconception Hb was associated with child Hb across the first 1000 d of life. However, preconception Hb was not a significant predictor of birth outcomes or cognitive outcomes at 6-7 y in this cohort from Vietnam.