Effects of heavy prenatal alcohol exposure and iron deficiency anemia on child growth and body composition through age 9 years

Abstract

Background: Prenatal alcohol exposure has been associated with pre- and postnatal growth restriction, but little is known about the natural history of this restriction throughout childhood or the effects of prenatal alcohol on body composition. The objective of this study was to examine the effects of heavy prenatal alcohol exposure on longitudinal growth and body composition.

Methods: Eighty-five heavy drinking pregnant women (≥2 drinks/d or ≥4 drinks/occasion) and 63 abstaining and light-drinking controls (<1 drink/d, no binging) were recruited at initiation of prenatal care in an urban obstetrical clinic in Cape Town, South Africa and prospectively interviewed during pregnancy about alcohol, smoking, drug use, and demographics. Among their children, length/height, weight, and head circumference were measured at 6.5 and 12 months and at 5 and 9 years. Percent body fat (BF) was estimated at age 9 years using bioelectric impedance analysis.

Results: In multiple regression models with repeated measures (adjusted for confounders), heavy alcohol exposure was associated with reductions in weight (0.6 SD), length/height (0.5 SD), and head circumference (0.9 cm) from 6.5 months to 9 years that were largely determined at birth. These effects were exacerbated by iron deficiency in infancy but were not modified by iron deficiency or measures of food security at 5 years. An alcohol-related postnatal delay in weight gain was seen at 12 months. Effects on head circumference were greater at age 9 than at other age points. Although heavy alcohol exposure was not associated with changes in body composition, children with fetal alcohol syndrome (FAS) and partial fetal alcohol syndrome (PFAS) had lower percent BF than heavy exposed nonsyndromal and control children.

Conclusions: Heavy prenatal alcohol exposure is related to prenatal growth restriction that persists through age 9 years and an additional delay in weight gain during infancy. FAS and PFAS diagnoses are associated with leaner body composition in later childhood.

Figure 1

Estimated marginal means for child growth indices by prenatal alcohol exposure status (with 95% CI; adjusted for confounders selected in multiple regression models (see Table 2); Z-scores based on CDC (2000) reference standards) ^†p ≤ .10. *p ≤ .05. **p ≤ .01