What are affects of a 4 vessel umbilical cord?

I am adopted and recently discovered an abnormality listed on my birth records as having a 4 vessel umbilical cord.  Being pregnant myself I am of course concerned and am unable to find out much on this topic. How does that happen? How often does it happen? What are the birth defects associated? Is it genetic? I am struggling to find any information on this topic and also if I should be concerned about health risks for me today

[Karichia2013]

Hi!
Here is a good link for information and pictures about 4 vessel umbilical cords:
http://www.sonoworld.com/Fetus/page.aspx?id=1149
There are some articles that suggest that a 4 vessel cord is correlated with multiple congenital anomalies.  These should all (or most) be visible on ultrasound.  I could also find several case reports of normal infants born with 4 vessels in the cord.  It depends a lot on whether the extra vessel is a vein or an artery, with arteries being much less significant.  In fact up to 5% of umbilical cords have an extra vein at some point in their length.  
I hope it helps
Good luck xxx