Predicting Fetal Prognosis by Assessing Fetal and Maternal Blood Flow Patterns in Pregnancies with Fetal Growth Restriction

Introduction. Fetal growth restriction (FGR) is associated with prematurity and a number of complications, as well as long-term impact on metabolic or cardiac function in adults. Aim of the Study. To study the prognostic value of staging maternal and fetal Doppler blood flow velocities in women with FGR; and evaluate prenatal characteristics as possible risk factors for severe vascular abnormalities. Materials and methods. 70 singleton pregnancies complicated by FGR were included in prospective follow-up study. Blood flow velocities in the uterine (UtA), umbilical (AU), middle cerebral (ACM) arteries and ductus venosus (DV) were measured. FGR neonates grouped as follows: I) normal blood velocity waveforms; II) abnormal UtA velocimetry and/or presence of early diastolic "notch"; III) abnormal AU without signs of "brain sparing"; IV) abnormal AU and ACM pulsatility index (PI) and V) AU absent or reversed end diastolic flow and an abnormal DV. Prenatal risk factors and perinatal outcome were assessed in relation to these Doppler blood flow patterns and compared with Fisher exact and Pearson c2 test. Results. There was a strong correlation between the severity of grouping and birth weight (p<0.001), gestational age at delivery (p<0.001), low amniotic fluid index (p<0.001), low Apgar scores (p=0.01) and neonatal transfer rate to NICU or hospital (p=0.02). Groups IV and V fetuses had the highest perinatal mortality (p=0.01). Women having genital infections (RTI) had significantly worse Doppler flow profile than non-smoking women at term without RTI (p=0.02). Conclusions. Severity of blood flow redistribution correlates with fetal morbidity and mortality. Less severe vascular changes, such as abnormal AU flow without centralization, and even increased uterine artery PI alone are linked to reduced birth weight, higher likelihood of preterm birth and increased risk of morbidity. Genital infections contribute significantly to hemodynamic changes related to the FGR. Screening and preventing of STI as well as optimizing the time of delivery may improve the overall outcome of compromised fetuses.