Effects of birth weight on growth and development and anemia among 6 – 23 months old infants in rural Hunan

Objective To examine the incidence of low birth weight and macrosomia in rural Hunan province, and to analyze effects of birth weight on growth and development and anemia among infants aged 6 – 23 months.

Methods A total of 3 630 infants aged 6 – 23 months in rural Hunan province were randomly selected with multistage sampling and probability proportion to size sampling at township-level. Questionnaire survey, body length and weight measurement, and peripheral blood hemoglobin detection were conducted among the participants between October and December 2017. Z-scores were used to evaluate the growth and development, and logistic regression model was used to adjust confounding factors for analyzing the effects of birth weight on growth and development and anemia.

Results The incidence of low birth weight was 4.10% (149/3 630) and that of macrosomia was 6.72% (244/3 630) for all the infants. Compared to those with normal birth weight or macrosomia, the infants with low birth weight had obviously higher prevalence rate of stunting (22.82% vs. 4.97% or 0.82%), underweight (14.09% vs. 2.35 % or 0.82%) and wasting (6.04% vs. 2.13% or 0.41%), suggesting that low birth weight was a risk factor for stunting (odds ratio OR = 7.91), underweight (OR = 6.25) and wasting (OR = 3.07). The prevalence rate of overweight/obesity was remarkably higher among infants with macrosomia than among those with low birth weight and normal birth weight (25.82% vs. 4.70% and 13.04%), indicating that macrosomia was a risk factor for overweight/obesity (OR = 2.27). The detection rate of anemia rate was 25.50%, 29.10%, and 25.41% among the infants with low birth weight, normal birth weight, and macrosomia, respectively, without significant difference in the rate among the three groups.

Conclusion There is a close association between birth weight and infants′ growth and development. Low birth weight could increase the risk of malnutrition among infants compared to normal birth weight, and macrosomia could increase the risk of overweight/obesity. Birth weight is not correlated with anemia in infants.