The first 1000 days after conception are critical for shaping brain health. Adverse events during this time can lead to neurodevelopmental, cognitive, and mental health problems across the life course. Early exposure to extrauterine life caused by premature birth is an adverse event affecting 15 million births globally—no treatments or strategies for protecting the brain after preterm birth exist. Professor Boardman will discuss how advanced neuroimaging techniques have revealed a cerebral signature of preterm birth, which includes alterations in the structural connectivity of developing brain networks. Drawing on recent studies from a richly phenotyped cohort of preterm infants, he will describe candidate biological axes that embed preterm birth in child brain development, focusing on systemic inflammation, nutrition, and the maternal and infant hypothalamic-pituitary-adrenal axis.