Fetal left inferior vena cava is a descriptor of an imaging test that usually refers to a variation in the anatomical location of fetal blood vessels and early medical attention is recommended. If a fetal left inferior vena cava is detected on prenatal ultrasound, there is no need to worry too much because it may be a simple variant of the anatomical location of the fetal inferior vena cava and does not indicate some serious problem with the fetal cardiovascular system, but this variant may also be combined with other cardiovascular developmental malformations, in which case further investigations need to be taken. If the results of the examination only indicate a simple left-sided inferior vena cava, the pregnant woman only needs to pay attention to the combination of work and rest, strengthen the pregnancy examination, and then review the examination after the birth of the child.