The umbilical vein provides convenient access to the central circulation of a neonate for restoration of blood volume and for administration of glucose and drugs.

More than two-thirds of fetal hepatic circulation is via the main portal vein, while the remainder is shunted from the left portal vein via the ductus venosus to the inferior vena cava, eventually being delivered to the fetal right atrium.

Under extreme pressure, the round ligament may reopen to allow the passage of blood.

Patients with cirrhosis experience rapid growth of scar tissue in and around the liver, often functionally obstructing nearby vessels.

[citation needed] A newborn baby has a patent umbilical vein for at least a week after birth.