Midline structures and cortical development in late‐onset fetal growth restriction according to Doppler status: prospective study

ABSTRACT Objectives Fetuses with late‐onset growth restriction (FGR) have a higher risk of suboptimal neurocognitive performance after birth. Previous studies have reported that impaired brain and cortical development can start in utero. The primary aim of this study was to report midline structure growth and cortical development in fetuses with late‐onset FGR according to its severity; the secondary aim was to elucidate whether the severity of FGR, as defined by the presence of abnormal Doppler findings, plays a role in affecting brain growth and maturation. Methods This was a prospective observational study that included fetuses with late‐onset FGR (defined according to the Delphi FGR criteria) undergoing neurosonography between 32 and 34 weeks' gestation. Midline structure (corpus callosum (CC) and cerebellar vermis (CV)) length and cortical development, including the depth of the Sylvian (SF), parieto‐occipital (POF) and calcarine (CF) fissures, were compared between late‐onset FGR, small‐for‐gestational‐age (SGA) and appropriate‐for‐gestational‐age (AGA) fetuses. Subgroup analysis according to the severity of FGR (normal vs abnormal fetal Doppler) was also performed. Univariate analysis was used to analyze the data. Results A total of 52 late‐onset FGR fetuses with normal Doppler findings, 60 late‐onset FGR fetuses with abnormal Doppler findings, 64 SGA fetuses and 100 AGA fetuses were included in the analysis. When comparing AGA controls with SGA fetuses, late‐onset FGR fetuses with normal Doppler findings and late‐onset FGR fetuses with abnormal Doppler findings, there was a progressive and significant reduction in the absolute values of the following parameters: CC length (median (interquartile range (IQR)), 43.5 (28.9–56.1) mm vs 41.9 (27.8–51.8) mm vs 38.5 (29.1–50.5) mm vs 31.7 (23.8–40.2) mm; K = 26.68; P