Association between postnatal catch-up growth and obesity in childhood: prospective cohort study

Objective To identify predictors of postnatal catch-up growth from birth to two years and its relation to size and obesity at five years. Design Regional prospective cohort study. Setting Avon longitudinal study of pregnancy and childhood, United Kingdom. Subjects 848 full term singletons from a 10% random sample of the Avon long itudinal study of pregnancy and childhood. Main outcome measures Maternal birth weight, prepregnancy weight pregnancy weight gain, height, smoking, and parity, and paternal height, Weight and l ength of infants at birth, two years, and five years expressed as standard deviation (SD) scores fr om the UK reference scores for 1990, Percentage fa t mass and total fat mass (estimated from skinfolds) and waist circumferenc e at five years. Results Size at birth was representative of die national reference. Overall , 30.7% (260 of 848) of infants showed a gain in SD score for weight greate r than 0.67 SD scores between zero and two years, indicating clinically sig nificant catch-up growth. These children had lower weight, length, and pond eral index at birth than other children, and were more often from primiparo us pregnancies. They also had taller fathers than other children, and their mothers had lower birth weights and were more likely to smoke during pregn ancy. Children who showed catch-up growth between zero and two years were h eavier, taller, and fatter (body mass index, percentage body fat, and waist circumference) at five years than other children. Conclusions Tn this contemporary well nourished cohort, catch-up growth was predicted by factors relating to intrauterine restraint of fetal growth. C hildren who showed catch-up growth between zero and two years were fatter a nd had more central fat distribution at five years than other children. Mec hanisms that signal and regulate early catch-up growth in the postnatal per iod may influence associations between small size at birth and risks for di sease in adulthood.