Main findings
The number of FGR cases defined by SMFM definition, ACOG definition and ISUOG definition were 115 (4.9%), 63 (2.7%) and 48 (2.1%) separately. There were 147 (6.28%) cases of SGA neonates and 127 (5.43%) cases complicated with ANO. As for predicting SGA or a composite ANO, the SMFM criteria had the highest sensitivity and NPV, while the ISUOG criteria had the highest specificity and positive predictive value. The AUCs of SMFM for predicting SGA (0.692) and ANO (0.566) were slightly higher than those of ACOG (0.616, 0.552) and ISUOG (0.598, 0.552).