Placental Pathology in Small-for-Gestational-Age Fetuses with Different Doppler Studies

Objectives: To describe and compare placental pathologies and neonatal outcomes in pregnancies with small-for-gestational-age (SGA) fetuses with their umbilical artery (UA) and middle cerebral artery (MCA) Doppler studies. Materials and Methods: A retrospective study was conducted in pregnant women delivered between gestational ages of 24 to 42 week at King Chulalongkorn Memorial Hospital. Only singletons without infection, chromosomal abnormalities or major structural abnormalities were included. Those with no Doppler study within 7 days prior to delivery were excluded. Sixty-nine subjects enrolled were classified into Group 1 (n=16): normal UA and MCA pulsatility index (PI), Group 2 (n=28): normal UA but abnormal MCA PI and Group 3 (n=25): abnormal UA PI/absent or reversed end diastolic flow (AREDF). Data were compared between each group. Results: Fetuses in Group 3 were found to be delivered at earlier gestational age with lower birth weight, higher Cesarean delivery rate, higher proportion of fetuses with Apgar score less than 7, higher NICU admission, and higher neonatal resuscitation rate than those in Group 1 and Group 2. There was no significant difference in placental weight, gross umbilical cord abnormality, and overall placental underperfusion pathology. Placental infarct in Group 3 was found to be more prevalent than those in Group 1 and Group 2. Conclusion: Placental infarct was the only abnormal placental pathology that was significantly found in SGA fetuses with abnormal UA PI/AREDF. These SGA fetuses carried a higher morbidity and mortality than those with normal UA Doppler study regardless of normality of MCA Doppler.