Preterm birth, defined as delivery <37 weeks’ gestation, is a major public health issue worldwide. An estimated 15 million babies are born preterm every year [1]. Preterm birth and the associated complications are now the leading cause of mortality in children under the age of 5 worldwide, accounting for 1 million deaths per year [2]. In the US, 11–12% of deliveries occur preterm, and worldwide, this figure is increasing. Babies born at ‘term’ – conventionally designated as 37–42 weeks’ gestation – have consistently better morbidity and mortality outcomes than those born before 37 weeks. In the short term, organ immaturity predisposes the preterm neonate to complications such as intraventricular hemorrhage and periventricular leukomalacia, necrotizing enterocolitis, and respiratory distress syndrome. Immaturity of the immune system increases the risk of neonatal sepsis, meningitis, and pneumonia. In the longer term, preterm babies have an increased prevalence of neurodevelopmental delay and chronic lung disease, and later in life, higher rates of adult-onset disease, from diabetes to hypertension and obesity [3]. Whilst extremely preterm (<28 weeks) and very preterm (28–32 weeks) neonates are at the highest risk of complications, studies have demonstrated that even late preterm birth (34 – 36 + 6 weeks) confers an increased risk of morbidity and mortality [4]. These effects appear to be pervasive, and as such premature infants have been shown to have lower educational attainment and employment than those born at term [5, 6].