Is there an association between isolated sonographic abdominal circumference below the 10th percentile and placental vascular lesions?

Objective: To study the association between prenatal diagnosis of isolated abdominal circumference (AC) below the 10th percentile (AC <10th) in appropriate for gestational age (AGA) neonates and placental vascular lesions.

Methods: A prospective study was conducted of healthy women who underwent sonographic fetal biometric measurements, up to 7 days before delivery, and delivered AGA neonates. The study cohort was divided into those with and without prenatal isolated AC <10th. Placental histopathology lesions were classified into maternal and fetal vascular malperfusion (MVM, FVM) lesions.

Results: Compared to the AC over 10th percentile group (n = 85), the AC <10th group (n = 85) was characterized by lower maternal body mass index, higher rate of smokers, and increased rate of induced labor (P = 0.029, P = 0.029, P = 0.001, respectively). There were no between-group differences regarding maternal age, gestational age, and neonatal outcome. Mean placental weight was lower in the isolated AC <10th (P < 0.001). The rate of MVM or FVM lesions did not differ between the groups. By multivariate logistic regression analysis, isolated AC <10th was not found to be associated with increased risk for placental vascular lesions.

Conclusion: Isolated AC <10th is associated with increased rate of induction of labor; however, it is not associated with increased placental vascular lesions.