Velamentous Cord Insertion

The umbilical cord normally inserts into the central portion of the placenta, well away from the placental edge. In a velamentous cord insertion, the umbilical cord inserts into the fetal membranes (choriamniotic membranes), then travels within the membranes to the placenta (between the amnion and the chorion). The exposed vessels are not protected by Whartons Jelly and hence are vulnerable to rupture.


Rupture is especially likely if the vessels are near the cervix, in which case they may rupture in early labor, likely resulting in a stillbirth. This serious condition is call Vasa Previa. Not every pregnancy with a velamentous cord insertion results in vasa previa, on those in which the blood vessels are near the cervix.


When a velamentous cord insertion is discovered, the obstetrician will monitor the pregnancy closely for the presence of vasa previa. If the the blood vessels are near the cervix, the baby will be delivered via C-section as early as 35 weeks to prevent the mother from going into labor, which would likely kill the baby. Early detection can reduce the need for emergency C-sections.

Below are some resources to learn more about velamentous cord insertion:

• http://radiopaedia.org/articles/velamentous-cord-insertion
• http://www.uptodate.com/contents/velamentous-umbilical-cord-insertion-and-vasa-previa
• http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3517836/

Here is a video that demonstrates how velamentous can be detected during an ultrasound.

My obstetrician, who delivered my son has told me that cord abnormalities like velamentous can most accurately be detected between 18-20 weeks. Currently, this is not routine in the U.S for most OB offices. However, the medical community is actively trying to raise awareness and make this detection a standard part of a second trimester ultrasound. 

Shepard's Velamentous Cord insertion

My pregnancy with Shepard was considered normal and low risk. I had two ultrasounds during my first trimester, one ultrasound in my second, and one ultrasound in my third trimester. Every ultrasound showed he was healthy and that he was on track for his gestational age. Our last ultrasound was only one week before we lost him and yet no-one detected the velamentous. Shepards velamentous was quite severe too. It was stretched roughly 4-6 inches away from the placenta.


I have been told by medical professionals that the people who did my ultrasounds were either not trained to detect the abnormalities or simply didn't take the time to look because these cord abnormalities are so rare. ( In the US velamentous occurs in roughly 1% of single pregnancies and 9% of multiple pregnancies.) Most of the time ultrasound techs just look to make sure there is blood flow from the placenta to the umbilical cord. They don't check the insertion points. 

I encourage people to be aware of these rare conditions and inform other pregnant women how simple it is to check for the cord insertion. It takes no more than 10 minutes on an ultrasound and it can mean the difference between life and death of the baby and possibly unnecessary emergency c-sections..