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Iron Supplementation in Pregnancy or Infancy and Motor Development: A Randomized Controlled Trial
Rosa M Angulo-Barroso1, Ming Li2, Denise C C Santos3
1Department of Kinesiology, California State University, Northridge, Northridge, California; Center for Human Growth and Development, and rosa.angulobarroso@csun.edu.
Insights
Iron supplementation during infancy significantly improved gross motor skills in 9-month-old babies. Supplementation during pregnancy did not show a similar effect on infant motor development.
Area of Science:
- Pediatric Nutrition
- Developmental Pediatrics
- Public Health Nutrition
Background:
- Iron deficiency is a significant concern for fetal and infant development.
- Optimal iron levels are crucial for cognitive and motor milestones.
Purpose of the Study:
- To evaluate the impact of iron supplementation during pregnancy and/or infancy on infant motor development at 9 months.
- To determine if iron supplementation timing influences motor outcomes.
Main Methods:
- A linked randomized controlled trial (RCT) design was employed in Hebei, China.
- Infants received either placebo or iron supplementation from 6 weeks to 9 months.
- Gross motor development was assessed using the Peabody Developmental Motor Scale, Second Edition.
Main Results:
- Iron supplementation in infancy, regardless of pregnancy supplementation, significantly improved gross motor scores (P < .001).
- Infancy iron supplementation led to a 0.3 standard deviation improvement in motor scores.
- Supplementation during pregnancy alone did not demonstrate a significant effect on infant motor development.
Conclusions:
- Iron supplementation in infancy causally improves gross motor development at 9 months.
- The timing of iron supplementation is critical, with infancy showing a clear benefit.
Background And Objective:
Insufficient iron levels for optimal fetal and infant development is a concern during pregnancy and infancy. The goal of this study was to assess the effects of iron supplementation in pregnancy and/or infancy on motor development at 9 months.
Methods:
The study was a randomized controlled trial (RCT) of infancy iron supplementation linked to an RCT of pregnancy iron supplementation, conducted in Hebei, China. A total of 1482 infants were randomly assigned to receive placebo (n = 730) or supplemental iron (n = 752) from 6 weeks to 9 months. Gross motor development (assessed by using the Peabody Developmental Motor Scale, Second Edition, instrument) was the primary outcome. Neurologic integrity and motor quality were secondary outcomes.
Results:
Motor outcome was available for 1196 infants, divided into 4 supplementation period groups: (1) placebo in pregnancy/placebo in infancy (n = 288); (2) placebo in pregnancy/iron in infancy (n = 305); (3) iron in pregnancy/placebo in infancy (n = 298); and (4) iron in pregnancy/iron in infancy (n = 305). Using the Peabody Developmental Motor Scale, instrument, iron supplementation in infancy but not pregnancy improved gross motor scores: overall, P < .001; reflexes, P = .03; stationary, P < .001; and locomotion, P < .001. Iron supplementation in infancy improved motor scores by 0.3 SD compared with no supplementation or supplementation during pregnancy alone. Effects of iron supplementation in infancy alone were similar to effects with iron in both pregnancy and infancy.
Conclusions:
The RCT design supports the causal inference that iron supplementation in infancy, with or without iron supplementation in pregnancy, improved gross motor test scores at 9 months.
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