Although supportive parenting has been shown to have positive effects on development, the neurobiological basis of supportive parenting has not been investigated. Thirty-three adolescents were systemically selected from a longitudinal study on child development based on maternal responsiveness during childhood, a measure of supportive parenting, and whether they were born term or preterm. We analyzed the effect of preterm birth on hemispheric and regional (frontal, temporal, parietal) cortical thickness and surface area using mixed-model analysis while also considering the effect of brain hemisphere (left vs. right). We then determined whether these factors were moderated by maternal responsiveness during childhood. Preterm birth was associated with regional and hemispheric differences in cortical thickness and surface area. Maternal responsiveness during childhood moderated hemispheric cortical thickness. Adolescence with mothers that were inconsistently responsive during childhood demonstrated greater overall cortical thickness and greater asymmetry in cortical thickness during adolescence as compared to adolescence with mothers who were consistently responsive or unresponsive during childhood. Maternal responsiveness and preterm birth did not interact. These data suggest that changes in brain morphology associated with preterm birth continue into adolescence and support the notion that the style of maternal-child interactions during childhood influence brain development into adolescence.