Exclusive Breastfeeding Measured by Deuterium-Oxide Turnover Method is Associated with Motor Development in Rural Senegalese Infants

Abstract

Background: The findings on the relationship between breastfeeding and children's motor development are very poor, particularly in low and middle income countries, because of the use of inadequate measures of breastfeeding practices.

Objectives: To assess the relationship between exclusive breastfeeding, measured by the deuterium-oxide turnover method (DTM), and the acquisition of motor development in a cohort of Senegalese children.

Methods: One hundred forty mother-infant (4-5 mo) pairs were recruited and monitored up to 18 mo. Breast milk intake and breastfeeding practices were measured by DTM. Six stages of motor development were assessed: "sitting without support," "hands-and-knees crawling," "standing with assistance," "walking with assistance," "standing alone," and "walking alone." Acquisition age of motor milestones between exclusively breastfed (EBF) and not exclusively breastfed (non-EBF) infants was compared using Student's and Wilcoxon's tests. Mixed linear regression, adjusted with confounding factors, was used to determine the association between EBF and motor development.

Results: Overall, 32.9% of infants were EBF at the enrollment at 4-5 mo of age. Breast milk intake of EBF infants was significantly higher than that of non-EBF infants (1039 ± 193 g/d compared with 915 ± 211 g/d; P < 0.01). At 4-5 mo of age, only "sitting without support" (67.4% compared with 47.9%, P = 0.02) and "hands-and-knees crawling" (17.4% compared with 4.3%, P = 0.01) were completed significantly in the EBF group. At 18 mo, all children had completed all 6 motor developmental milestones. However, their acquisition age was significantly earlier in the EBF group after adjustment. Non-EBF infants had a delay of 0.4 to 0.5 mo on the acquisition of the first 5 stages compared to EBF infants. For "walking alone," no difference was found after adjustment.

Conclusions: Motor skill acquisition is earlier in EBF infants compared to non-EBF infants. This finding highlights the need to strengthen the advocacy for EBF up to 6 mo.

Keywords: Senegal; breast milk intake; deuterium-oxide turnover method; exclusive breastfeeding; motor development.