Maternal postpartum nutrition exposures, breastfeeding, and infant weight

Objective: This dissertation investigated relationships between postpartum maternal dietary intakes, breastfeeding exclusivity, intensity, and duration, reasons for weaning before 6 months, and infant weight at 6 months. Methods: Three aims examined 8 nutritional exposures: magnesium, added sugar, dairy, energy, glycemic load, and macronutrient distributions (percent of calories from carbohydrate, protein, and fat) among participants in the United States Food and Drug Administration (FDA) and Centers for Disease Control and Prevention (CDC)’s second Infant Feeding Practices Study (IFPS II). The first aim employed logistic regression to examine the association between intakes of dietary factors and exclusive breastfeeding at 3 months, partial breastfeeding at 3 months, and any breastfeeding at 6 months (n = 1099). The second aim used logistic regression to investigate the association between intakes of dietary factors and reasons for early weaning (n = 587). The third aim used multivariable linear regression to examine differences in infant weight and weight-for-age z-scores at 6 months by intakes of dietary exposures (n =186). Unadjusted models and models adjusted for relevant covariates were executed. Results: Those with consumption at or exceeding recommended daily intakes of magnesium, dairy, and energy were more likely to engage in recommended breastfeeding behaviors. Consuming a diet with a low average daily glycemic load was associated with not breastfeeding as recommended. Low average daily glycemic load was associated with a lower likelihood of citing “too much milk” as a reason to wean. No maternal intakes were associated with higher or lower weight or weight-for-age z-scores at 6 months. Conclusion: Findings support existing nutrition guidelines for women of childbearing age, and suggest that a higher daily intake of magnesium may be appropriate for lactating mothers. Average daily glycemic load may also be important, and should be studied further. Implications: This dissertation provides an exploration into specific maternal dietary intakes and important outcomes of infant feeding. It provides a foundation for future inquiries into the roles of magnesium and glycemic load in supporting breastfeeding