When stratified by CHD type (Supplementary Materials Tables S3–S5), the same significantly lower PlGF staining pattern in the syncytiotrophoblast was observed in placentas from pregnancies with atrioventricular septal defect (AVSD) and ventricular septal defect (VSD) fetuses, but not in hypoplastic left heart syndrome (HLHS) cases. This evidence concerns the gene PGF and hypoplastic left heart syndrome.