Factors Predicting Fetal Growth Restriction and Fetal Cardiac Remodeling.

Objective: This study aimed to investigate factors influencing fetal growth restriction (FGR) occurrence and assess the clinical significance of fetal cardiac parameters in FGR prediction.

Methods: Pregnant women with clinically suspected FGR (n=179) and uncomplicated pregnancies (n=53) were included. All had undergone routine obstetric ultrasonography and fetal echocardiography. Umbilical artery flow (UAF) and fetal cardiac parameters (left atrial transverse diameter (LAd), right atrial transverse diameter (RAd), left ventricular transverse diameter (LVd), right ventricular transverse diameter (RVd), foramen ovale width, atrial septum diameter, interventricular septal thickness, left ventricular posterior wall thickness, right ventricular free wall thickness, aortic diameter, pulmonary artery diameter, mitral E velocity, mitral A velocity, tricuspid E velocity, tricuspid A velocity, aortic valve peak flow velocity, and pulmonary valve peak flow velocity) were detected. Follow up was conducted until birth, various fetal clinical parameters were collected: maternal body mass index (BMI), hypertensive disorders complicating pregnancy (HDCP), abnormal umbilical artery flow, placental or umbilical cord anomalies, low amniotic fluid volume, preterm birth, emergency cesarean delivery, maternal height, maternal age, gestational diabetes mellitus (GDM), hypothyroidism, assisted reproductive technology (ART), parity, and neonatal gender. Participants were categorized into confirmed FGR (n=119) and control (n=113) groups based on neonatal birth weight.

Results: Significant differences were observed between groups in maternal BMI, HDCP, abnormal UAF, placental or umbilical cord anomalies, low amniotic fluid volume, preterm birth, and emergency cesarean delivery. FGR was positively related to abnormal UAF, placental or umbilical cord anomalies, preterm birth and emergency cesarean delivery and negatively to maternal BMI (r=-0.276). Compared to the control group, the FGR group exhibited significantly larger RAd, RVd, RA/LA, and RV/LV.

Conclusion: Fetal growth-restricted fetuses have enlarged right heart structures. Fetal cardiac examinations are valuable for early FGR diagnosis, potentially improving neonatal body weight and reducing adverse pregnancy outcomes.