Fetal and infant growth and asthma symptoms in preschool children: the Generation R Study.

RATIONALE: Low birth weight is associated with an increased risk of wheezing in childhood.

OBJECTIVES: We examined the associations of longitudinally measured fetal and infant growth patterns with the risks of asthma symptoms in preschool children.

METHODS: This study was embedded in a population-based prospective cohort study among 5,125 children. Second- and third-trimester fetal growth characteristics (head circumference, femur length, abdominal circumference, and weight) were estimated by repeated ultrasounds. Infant growth (head circumference, length, and weight) was measured at birth and at the ages of 3, 6, and 12 months. Parental report of asthma symptoms until the age of 4 years was yearly obtained by questionnaires.

MEASUREMENTS AND MAIN RESULTS: Both fetal restricted and accelerated growth, defined as a negative or positive change of more than 0.67 standard deviation score, were not associated with asthma symptoms until the age of 4 years. Accelerated weight gain from birth to 3 months following normal fetal growth was associated with increased risks of asthma symptoms (overall odds ratio for wheezing: 1.44 [95% confidence interval: 1.22, 1.70]; shortness of breath: 1.32 [1.12, 1.56]; dry cough: 1.16 [1.01, 1.34]; persistent phlegm: 1.30 [1.07, 1.58]), but not with eczema (0.95 [0.80, 1.14]). These associations were independent of other fetal growth patterns and tended to be stronger for children of atopic mothers than for children of nonatopic mothers.

CONCLUSIONS: Weight-gain acceleration in early infancy was associated with increased risks of asthma symptoms in preschool children, independent of fetal growth. Early infancy might be a critical period for the development of asthma.