Differences in Sensorimotor Development Among U.S. Infants Receiving Breastmilk and/or Formula in the First 6-Months From the PediaTrac™ Project

Abstract

ObjectivesAchieving sensorimotor (SEM) milestones is one measure of early infant brain development promoted through higher docosahexaenoic acid (DHA) levels. Both breastmilk and formula contain DHA, with a global level of 0.32% in breastmilk and many formula brands. However, a 2017 study of Midwestern U.S. mothers found significantly lower breastmilk DHA levels. It was thus hypothesized that infants fed formula would have higher SEM scores. The objective of this study was to measure differences in SEM development between infants fed breastmilk, formula, or a combination in participants of the PediaTrac™ Project. PediaTrac is a web-based measure providing longitudinal, real time, multidomain data on infant and toddler growth and development at time periods corresponding to well child visits. MethodsUsing PediaTrac, data were collected from 548 caregiver-infant dyads across multiple Midwestern sites. Caregivers reported the primary nutrition source as breastfeeding, formula or combination. Their responses to gross and fine motor function questions were used to create a SEM composite, Percent of Maximum Possible (POMP) score at newborn (NB), 2-, 4- and 6-months. Data were analyzed via ANOVA and Tukey test using SPSS. ResultsInfants fed formula had statistically higher mean SEM scores at NB (M = 0.618Formula, M = 0.590Breast, p = 0.017), 2- (M = 0.706Formula, M = 0.680Breast, p = 0.006) and 6-months (M = 0.727Formula, M = 0.696Breast, p = 0.014) compared to breastfed infants. Mean SEM scores of combination fed infants were higher than breastfed infants at 2- (M = 0.701Combination, M = 0.680Breast, p = 0.184), 4- (M = 0.684Combination, M = 0.673Breast, p = 0.573) and 6-months (M = 0.704Combination, M = 0.696Breast, p = 0.895), despite no significant differences between scores. ConclusionsFormula fed infants showed consistently higher SEM scores than breastfed infants in the first 6-months. These findings contradict previous research, indicating a need for further investigation into variables contributing to these discrepancies such as maternal breastmilk DHA concentrations, socioeconomic factors, site specific confounds, accuracy of parent reports of motor development, etc. Funding SourcesEunice Kennedy Shriver National Institute of Child Health & Human Development of the National Institutes of Health. EMU College of Health & Human Services Research Support Award.