Indeed, a longitudinal study of 55 babies with a birthweight below the 5th percentile reported that, despite increased insulin sensitivity at birth, insulin resistance had developed by 3 years of age and was correlated with degree of‘catch-up’, or accelerated postnatal, growth.The relationship between insulin sensitivity and accelerated postnatal growth was already present at 1 year of age in another cohort of SGA babies.
Similarfindings were reported for IGF-1 concentrations, which were decreased at birth in
SGA infants but increased at 3 years, indicative of relative IGF-1 resistance, and correlated with degree of accelerated postnatal growth between birth and 3 years.