What are the other Names for this Condition? (Also known as/Synonyms)

• UVV (Umbilical Vein Varix)

What is Umbilical Vein Varix? (Definition/Background Information)

• The placenta is an organ that connects the developing fetus to the uterine wall. It is a disc shaped reddish brown structure that connects the fetus to the mother through the umbilical cord. The normal function of placenta is to supply nutrients and oxygen to the fetus from the mother’s blood and remove wastes from the fetal body
• The umbilical cord contains two umbilical arteries and one umbilical vein, providing a connection between maternal and fetal blood circulation
• Umbilical Vein Varix (UVV) is a variceal dilatation (enlargement/swelling) of the umbilical vein. It can arise either from the intra-abdominal or extra-abdominal part of the umbilical cord. When the intra-abdominal region is involved, UVV is also referred to as Fetal Intra-Abdominal Umbilical Vein Varix (or FIUVV) in medical literature
• Umbilical Vein Varix can occur in isolation or be associated with chromosomal anomalies, cardiovascular abnormalities, fetal hydrops, fetal anemia-related complications, umbilical vessel abnormalities, intrauterine growth restriction, and even result in intrauterine fetal death
• Umbilical Vein Varix requires prompt and appropriate treatment for an optimal outcome. The prognosis of UVV is generally dependent upon the severity of the condition and the presence of any associated abnormalities

Who gets Umbilical Vein Varix? (Age and Incidence)

• The exact incidence of Umbilical Vein Varix is not known. According to literature the incidence is low, ranging from 4 to 11 cases per 10,000 pregnancies
• It can occur in pregnant women of any age. And, both male and female fetuses can be affected
• All racial and ethnic groups may be affected, and no specific preference is observed

What are the Risk Factors for Umbilical Vein Varix? (Predisposing Factors)

• There are no clearly identified risk factors for Umbilical Vein Varix in many cases
• In some cases, the condition is reportedly associated with chromosomal anomalies such as trisomy 18, trisomy 21, trisomy 9, triploidy, and mosaic Turner syndrome

It is important to note that having a risk factor does not mean that one will get the condition. A risk factor increases one’s chances of getting a condition compared to an individual without the risk factors. Some risk factors are more important than others.

Also, not having a risk factor does not mean that an individual will not get the condition. It is always important to discuss the effect of risk factors with your healthcare provider.

What are the Causes of Umbilical Vein Varix? (Etiology)

The abnormal development of umbilical vein during fetal growth causes Umbilical Vein Varix (UVV).

• In this condition, there is a dilatation of the umbilical vein in either the intra-abdominal or extra-abdominal umbilical cord portion of the umbilical vein. Intra-abdominal UVV is also known as Fetal Intra-Abdominal Umbilical Vein Varix (FIUVV)
• UVV is known to be associated with certain chromosomal anomalies including trisomies

What are the Signs and Symptoms of Umbilical Vein Varix?

The signs and symptoms of Umbilical Vein Varix (UVV) depend on whether it is the isolated form or if it is associated with other congenital syndromes.

• In cases of UVV, especially the isolated form, there are rarely any associated symptoms noted
• However, the non-isolated forms of UVV may present fetal distress due to thrombosis in the varix along-with other complications and associated abnormalities
• In such cases, significant signs and symptoms of the underlying chromosomal abnormalities may also be noted

How is Umbilical Vein Varix Diagnosed?

The diagnosis of Umbilical Vein Varix may involve:

• Physical examination along with an evaluation of one’s medical history: The healthcare provider may check for any signs of fetal distress (such as non-reassuring fetal heart rate)
• Prenatal abdominal ultrasound may reveal the condition and other associated fetal abnormalities
• Amniocentesis to detect chromosomal abnormalities
• A careful examination of the placenta, particularly the umbilical cord after birth of the child, may help establish a definitive diagnosis

Many clinical conditions may have similar signs and symptoms. Your healthcare provider may perform additional tests to rule out other clinical conditions to arrive at a definitive diagnosis.

What are the possible Complications of Umbilical Vein Varix?

The complications of Umbilical Vein Varix depend on whether it is the isolated form or non-isolated form, in which case it is associated with certain congenital anomalies. When present in isolated form, there are no significant complications noted.

The complications of Umbilical Vein Varix, if associated with congenital anomalies, may include:

• Intrauterine growth restriction resulting in decreased fetal growth
• Turbulent flow within the varix (necessitating close monitoring of the fetus)
• Hydrops fetalis - a serious fetal condition defined as an abnormal accumulation of fluid
• Thrombus (blood clot) within the varix that may lead to fetal compromise, necessitating prompt delivery of the baby
• Intrauterine fetal death

How is Umbilical Vein Varix Treated?

The treatment depends on factors such as whether Umbilical Vein Varix (UVV) is an isolated event or is observed in the background of other congenital anomalies.

• In isolated cases, no treatment may be necessary, apart from close monitoring of the fetal development through regular prenatal visits
• In case of UVV being associated with other fetal abnormalities/defects, a careful and periodic monitoring of the pregnancy is necessary, as such abnormalities typically present thrombosis, growth restriction, and may even cause fetal demise
• Management may involve induction of labor before term, or Cesarean sections based on individual clinical settings such as the presence of thrombosis, size of the varix, flow abnormalities, and fetal distress

How can Umbilical Vein Varix be Prevented?

• Currently, there are no definitive methods available to prevent Umbilical Vein Varix
• A careful and periodic monitoring of the pregnancy is advised and recommended

What is the Prognosis of Umbilical Vein Varix? (Outcomes/Resolutions)

• Isolated cases of Umbilical Vein Varix are mostly associated with favorable outcomes
• However, close monitoring is necessary in order to promptly detect some ominous signs such as turbulent flow, thrombosis, or fetal distress
• The rate of fetal mortality in cases of Umbilical Vein Varix with associated anomalies and chromosomal abnormalities is reportedly high

Additional and Relevant Useful Information for Umbilical Vein Varix:

The following DoveMed website link is a useful resource for additional information:

https://www.dovemed.com/diseases-conditions/pregnancy-related-disorders/