Clinical characteristics for chronic hypoxia cohort: severe preterm FGR.

Data is presented as mean (SEM), median (IQR) or percentage.REDF: reversed end diastolic flow. AEDF: absence end diastolic flow. ↑PI: increased pulsitility index with positive end diastolic flow. (The progression from increased PI to REDF in the umbilical artery represents increasing placental resistance and therefore is an indirect measure of the severity of fetal growth restriction due to placental insufficiency).