A closer look at the fetal programming hypothesis with obstetric ultrasound

Most, if not all, pregnant women in developed countries will have an ultrasound examination to time pregnancy and assess the health and development of the embryo or fetus. Nonetheless, surprisingly few cohort studies have used routine health care or research ultrasound data to test their hypotheses. Repeated ultrasound assessments during pregnancy offer the opportunity to examine the association of intra-uterine exposures with fetal growth and the association of fetal growth patterns with child outcomes. Most studies of fetal programming simply rely on a proxy measurement of fetal growth: maternal or midwife report of birth weight. Birth outcomes are only crude summary measures of fetal growth and cannot provide information on growth across different times in pregnancy. Furthermore, individuals may reach the same birth weight through different fetal growth trajectories. Pinto et al. are to be complimented for the use standardized clinical ultrasound conducted by one clinician to test an important public health question: do children of anxious or depressed mothers have a worse start to life even before they are born?