(1004) Early Placental Volume as a Biomarker for Maternal Vascular Malperfusion

Early placental volume (PV) is associated with fetal growth outcomes, but manual segmentation makes it clinically infeasible. Novel automated techniques have made 3D placental biometry more clinically practical; yet, it is unclear whether PV can distinguish constitutionally small fetuses from affected by placental insufficiency. Such a distinction is critical for developing targeted interventions and improving pregnancy outcomes. We sought to explore whether early PV, measured by an automated segmentation tool, is associated with placental pathology.

Study Design:

In this prospective, longitudinal cohort study, 3DUS volumes of the placenta were obtained at 11-16 weeks (V1) and 18-24 weeks (V2). Automated segmentation tools developed in our lab were utilized to measure PV, which were normalized to gestational age. Placentas were examined by a trained placental pathologist blinded to the PVs. Outcomes included birth weight (BW), birth weight centile (BW%), placental weight (PW), placental weight z-score, and high grade maternal (MVM) or fetal (FVM) vascular malperfusion on the delivered placenta. Given the sample size, analyses were unadjusted.

Results:

72 subjects had a V1PV and available outcomes, 65 of which also had a V2PV. MVM and FVM was identified in 12.3% (n=8) and 13.9% (n=9) of placentas, respectively. V1PV (mean: 6.4±1.8 cc/wk) was significantly correlated with BW (mean: 3144.9±548g; p=0.007) and BW %ile (mean: 42.8±25.6; p=0.03). V1PV was significantly smaller in cases with MVM (mean: 5.3 vs 6.9cc, p=0.039). V2PV (mean: 11.3±2.9 cc/wk) was significantly correlated with PW (mean: 463.7±98g; p=0.02), PW z-score (mean: –0.5±1.3; p=0.02), and showed a trend towards association with BW (p=0.06) and MVM (p=0.06). Table

Conclusion:

Novel segmentation tools can measure PV in an automated fashion to generate a biomarker of fetal growth outcomes. Our results demonstrate that early PV may be used to identify placental maldevelopment in pregnancy, where early identification can significantly improve patients’ counseling and clinical management.