Associations of fetal growth patterns and growth in the first two years of life: a longitudinal study of a Beijing birth cohort

BACKGROUND: This study aimed to evaluate the association between fetal growth patterns and early childhood growth rate. METHODS: In total, 6,370 mother-child pairs were included in a birth cohort in Beijing. Fetal biometric parameters were measured at 20-24, 28-32, 33-36 weeks, and at ≥37 weeks of gestation, and infant weight and length were assessed from birth to 24 months of age. Changes in the weight-for-length Z-score (WLZ) from birth to 3, 6, 9, 12, 18, and 24 months of age were used to classify infant growth velocity as slow (change in WLZ < -0.67) and or rapid (change in WLZ >0.67). A group-based trajectory model was used to identify fetal growth patterns. Generalised linear models and longitudinal modified Poisson GEE models were used to assess the association between fetal trajectories and infant growth velocity. RESULTS: Five fetal growth patterns were identified. Early acceleration with late decline and a moderate final Z score (EALD-M) showed no obvious trend in growth rate from birth to 24 months of age. Early deceleration (ED) was significantly associated with an increased risk of rapid growth at 3, 6, 9, 12, 18, and 24 months (risk ratio [RR] = 1.93-2.56), followed by stable growth (SG) (RR = 1.47-1.74). Early acceleration with late decline and high final Z score (EALD-H) was associated with an increased risk of slow growth at 3, 6, 9, 12, 18, and 24 months (RR = 1.64-2.02), followed by late acceleration growth (LA) (RR = 1.26-1.48). CONCLUSION: ED and SG are associated with rapid growth, whereas LA and EALD-H are associated with slow growth.