Pre-pregnancy obesity and maternal nutritional biomarker status during pregnancy: a factor analysis.

OBJECTIVE: Pre-pregnancy obesity has been associated with adverse birth outcomes. Poor essential fatty acid (EFA) and micronutrient status during pregnancy may contribute to these associations. We assessed the associations between pre-pregnancy BMI and nutritional patterns of maternal micronutrient and EFA status during mid-pregnancy. DESIGN: A cross-sectional analysis from a prospective cohort study. Women provided non-fasting blood samples at ≥ 20 weeks' gestation that were assayed for red cell EFA; plasma folate, homocysteine and ascorbic acid; and serum retinol, 25-hydroxyvitamin D, a-tocopherol, soluble transferrin receptors and carotenoids. These nutritional biomarkers were employed in a factor analysis and three patterns were derived: EFA, Micronutrients and Carotenoids. SETTING: The Antidepressant Use During Pregnancy Study, Pittsburgh, PA, USA. SUBJECTS: Pregnant women (n 129). RESULTS: After adjustment for parity, race/ethnicity and age, obese pregnant women were 3.0 (95% CI 1.1, 7.7) times more likely to be in the lowest tertile of the EFA pattern and 4.5 (95% CI 1.7, 12.3) times more likely to be in the lowest tertile of the Carotenoid pattern compared with their lean counterparts. We found no association between pre-pregnancy obesity and the Micronutrient pattern after confounder adjustment. CONCLUSIONS: Our results suggest that obese pregnant women have diminished EFA and carotenoid concentrations.