Magnetic Resonance Imaging in Pregnancy with Intrauterine Growth Restriction: A Pilot Study.

OBJECTIVE: Intrauterine growth restriction (IUGR) is a major cause of late stillbirth, though not all compromised babies remain small or are considered growth restricted as pregnancy progresses. Fetal Magnetic Resonance Imaging (f-MRI) represents a second-line tool to study pregnancies with IUGR fetuses. The aim of our study was to evaluate the usefulness of f-MRI on predicting fetal growth and the offspring's perinatal respiratory outcome. DESIGN: All f-MRI performed between 2014 and 2016 in Siena were analysed. Pregnancies with IUGR (Study group (SG)) were recruited together with a control population (Control group (CG)), coupled for gestational age (GA) at the time of f-MRI (mean GA 31 wks). Neonatal information was collected. The f-MRI protocol consisted of T2w images. Six regions of interest (ROI) were placed as follows: 2 on the lung, 2 on the liver, and 2 on the amniotic fluid. The signal intensities (SI) of each ROI were measured. The SI lung to liver ratio (SI lung/liver) and SI lung to amniotic fluid ratio (SI lung/amniotic fluid) were obtained for each fetus. Each ratio was compared between SG and CG. Therefore, SG was divided into two subgroups: adequate and small for gestational age (AGA and SGA) newborns. All measurements were related to offspring's perinatal respiratory outcome. RESULTS: SI lung/liver was linearly related with GA at the time of f-MRI and with EFW. SI lung/amniotic fluid was significantly higher in SG than in CG (p = 0,014). In contrast, among SG, lower values of SI lung/amniotic fluid were found in the SGA compared to AGA (p = 0,036). The days of oxygen supply were higher in the SGA subgroup than in the AGA subgroup (p = 0,028). CONCLUSIONS: SI lung/liver increases with fetal lung maturation and appears to be useful to estimate intrauterine fetal growth. SI lung/amniotic fluid seems to be a reliable predictive index to distinguish the IUGR fetuses that can recover their growth from those that were born SGA. f-MRI represents a promising frontier to predict IUGR fetus outcome, thus contributing to ameliorate the perinatal management.

Placental histological examination and the relationship with oxidative stress in preterm infants.

BACKGROUND: Prenatal conditions of enhanced oxidative stress (OS) linked to inflammation or hypoxia have been associated with impaired fetal growth and preterm delivery. Little is known regarding biomarkers of OS in the cord blood of preterm infants and placental histological patterns. OBJECTIVES: To test the hypothesis that placental lesions indicating chorioamnionitis (CA) or vascular underperfusion (VU) are associated with increased OS in the offspring. METHODS: 120 neonates born below 29+6 weeks of gestational age (GA) were enrolled. Histological characteristics of placentas from their mothers were classified as normal (CTRL group), histological CA (HCA) and vascular underperfusion (VU). Serum concentrations of isoprostanes (IsoPs), non-protein bound iron (NPBI) and advanced oxidative protein products (AOPP), were determined in cord blood. RESULTS: IsoPs, NPBI and AOPP were significantly increased in HCA group compared to CTRL group. The multivariable regression model, adjusted for GA, maternal age, parity, maternal diabetes, maternal obesity and presence/absence of fetal growth restriction (FGR), showed a significant association between the presence of HCA and increased OS biomarkers levels in cord blood (IsoPs: p = 0.006; NPBI: p = 0.014; AOPP: p = 0.007). Placental VU lesions were significantly associated with higher umbilical IsoPs, NPBI and AOPP levels (IsoPs: p = 0.008; NPBI: p = 0.002; AOPP: p = 0.040). In the cases of placental VU lesions associations were also found between high AOPP levels and low GA (p = 0.002) and the presence of fetal growth restriction (p = 0.014). CONCLUSIONS: Placental lesions indicating inflammation or impaired perfusion are associated with higher cord blood levels of OS biomarkers explaining the fetal susceptibility to oxidative injury and the need of antioxidant protection.