Portosystemic venous shunts (PSVS) are malformations that result from abnormal communications between the portal and hepatic veins or inferior vena cava. Prenatal diagnosis is made by evaluating the fetal venous circulation and it is classified as intrahepatic and extrahepatic, with different evolution and complications. Objective: To report two cases of prenatal diagnosis of portosystemic vascular shunts and review the importance of this rare pathology in its neonatal and pediatric evolution. Clinical Cases: Case 1: pregnancy with fetal growth restriction, 2nd percentile, polyhydramnios, without fetal malformations and abnormal patterns on fetal Doppler. Abnormal blood flow through the ductus venous and abnormal venous communication in the liver were identified. Normal genetic study. Male newborn (NB) delivered at 36 weeks, because of severe fetal growth restriction, by emergency cesarean section. He evolved asymptomatic, with normal liver function, and did not continue follow-up. Case 2: pregnancy with fetal growth restriction < percentile 1. Agenesis of the ductus venous and abnormal communication between the portal vein and the left suprahepatic vein were identified with no other malformations or signs of heart failure. Severe SGA newborn was delivered by induction of labor at 35 weeks. He evolved asymptomatic. Normal complementary study. A home check-up at 2 months showed persistent vascular anomaly without systemic involvement. Conclusions: Even though in the cases presented there were no neonatal complications, this kind of malformations require a high index of suspicion in cases with fetal growth restriction, as well as a long-term multidisciplinary follow-up.