Evidence From Epidemiological Studies: Preterm Birth and an Increased Risk of Developing Hypertension

Preterm Birth The majority of epidemiological studies in developmental programming have explored the influence of low birth weight (irrespective of gestational age) on long-term chronic disease in individuals born during the first half of the 20th century. Low birth weight neonates may represent infants born at term with intrauterine growth restriction (IUGR) or born preterm with or without IUGR. As such, there is emerging interest in the effects of preterm birth alone (beyond birth weight and IUGR) on specific aspects of human development and long-term health. Approximately 10% of all births worldwide are preterm (before 37 completed weeks of gestation). Besides being of low birth weight, preterm neonates are suddenly and prematurely exposed to the extrauterine environment at a time when organogenesis is incomplete. Exposure postnatally to factors such as high oxygen concentrations, medications (including glucocorticoids), and inadequate nutrition likely adversely influence postnatal growth and ongoing organ development. In addition to possible genetic and epigenetic factors that may contribute to hypertension risk (including hypertension-related complications of pregnancy), a multitude of aspects related to both intrauterine and extrauterine growth, as well as the postnatal environment, may all play an important role in the programming of hypertension in individuals born preterm. In this review, we will highlight, in particular, the potential effect of oxidative stress associated with preterm birth on neonatal development and future disease risk.