Maternal Hemoglobin Concentrations Across Pregnancy and Child Health and Development From Birth Through 6 y

OBJECTIVES: The importance of timing of changes in maternal hemoglobin (Hb) across preconception and pregnancy on child health and development (CHD) remains unclear. We examined the association with maternal Hb trajectories and CHD outcomes: a) birth outcomes (birth weight, length, gestational age, preterm and small for gestational age) b) child Hb at 3 mo, 1 y, and 2 y c) motor and mental development at 1 y and 2 y (Bayley scales for infant development) and cognitive functioning at age 6 y (Wechsler Intelligence Scale for Children). METHODS: We used data from a randomized controlled trial (PRECONCEPT) conducted in Vietnam. Current analysis includes 1175 women with singleton birth and preconception and pregnancy Hb data. Maternal Hb trajectories were developed using maternal Hb data at preconception, early (≤20 wks), mid (21–29 wks), and late (≥30 wks) pregnancy. Multivariable linear and logistic regression models were used to assess the association between maternal hemoglobin trajectories on CHD outcomes, adjusting for confounding variables at the maternal, child and household levels. RESULTS: Four distinct maternal Hb trajectories were identified. Track 1 included women who were anemic at preconception and Hb remaining low (Hb < 11 g/dl) throughout pregnancy (7.5%). Track 2 included women who were anemic at preconception with Hb recovering early in pregnancy and remaining above 11 g/dL throughout pregnancy (1.7%). Track 3 included women who were non-anemic at preconception and dropping to a low of 11 g/dL in mid pregnancy (55%). Track 4 include women with high preconception Hb (13–14 g/dL) who were non-anemic throughout preconception and pregnancy (36%). Maternal Hb trajectories were not significantly associated with birth outcomes. Track 4 was associated with significantly higher child Hb at 3, 6 and 12 months and child motor development at 12 mo compared to track 1. Maternal Hb trajectories were not associated with child development at 24 mo or 6 y. CONCLUSIONS: Maintaining an elevated Hb (> 12 g/dL) across preconception and pregnancy was associated with improved child hemoglobin in the first year of life, but did not predict birth outcomes or child development after age 2 y. FUNDING SOURCES: NIH (1R03HD102513-01), Nestle Foundation, Micronutrient Initiative, Mathile Institute for Advancement of Human Nutrition.