First-trimester measurements of the three-dimensional ultrasound placental volume and uterine artery Doppler in early- and late-onset fetal growth restriction.

To clarify whether early-onset fetal growth restriction (EO-FGR) could be distinguished from late-onset (LO)-FGR using ultrasonographic evaluations of the uterine artery (UtA) Doppler indices and the three-dimensional (3D) ultrasound placental volume (PV) in the first trimester. Subjects with 1362 singleton pregnancies who underwent an ultrasound scan at 11-13 weeks were enrolled prospectively. The UtA Doppler and PV indices in cases with EO-FGR (<32 weeks at diagnosis) and LO-FGR (≥32 weeks at diagnosis) later in pregnancy were compared with the control group. Twenty-eight EO-FGR, 73 LO-FGR, and 1261 control groups were analyzed. The crown-rump length (CRL) and PV were smaller in both EO and LO-FGR groups than in the control group. The UtA resistance index (RI) -score was significantly higher in the EO-FGR group than in the control group (0.723 versus 0.086,  < .001), but did not differ between LO-FGR and the control group. The area under the receiver operating characteristics curve for the prediction of EO-FGR by combining the uterine artery resistance index (UtA-RI) and CRL was 0.760 (95% CI: 0.654-0.865). The detection rate for EO-FGR was 45.8%, with a 10% false-positive rate. Both EO- and LO-FGR are associated with a small CRL in the first trimester. High UtA-RI is associated with EO-FGR, while a small maternal height and PV are associated with LO-FGR.