Abstract
OBJECTIVE: To characterize restricted and repetitive behaviors (RRBs) and reciprocal social behaviors (RSBs) in a large sample of toddlers who represent a range of birth weights and gestation durations. STUDY DESIGN: A battery of questionnaires characterizing demographic information and measuring RRBs and RSBs were completed by parents of toddlers between the ages of 17-26 months (n = 1589 total; n = 98 preterm). The association between birth weight and/or gestation duration and the primary outcome measures (RRBs and RSBs as ascertained through the Repetitive Behavior Scale for Early Childhood and the Video-Referenced Rating of Reciprocal Social Behavior) were tested by using hierarchical multivariate multiple regression. RESULTS: Toddlers born preterm and full term did not differ on RRBs or RSBs. However, there were significant associations between birth weight percentile for gestation duration (BPGD) and RRBs (β = -2.1, P = .03), above and beyond the effects of age, sex, and vocabulary production. Similarly, there was a significant association between BPGD and RSBs (β = -1.8, P = .02), above and beyond the effects of age, sex, and vocabulary production. CONCLUSIONS: These findings demonstrate that BPGD better predicted putative antecedents of adverse psychological outcomes-specifically, RRBs and RSBs-than gestation duration alone. These findings provide insight to the link between preterm birth and suboptimal behavioral/psychological outcomes and suggest that high birth weight, which may reflect a more optimal intrauterine environment, may serve as a protective factor irrespective of gestation duration.