Everything you never wanted to know about umbilical cords

The umbilical cord: weird, rubbery and attached to the thing (the placenta) dead last on your husband's list of "things I'd most like to see." It is as amazing as it is odd, and is literally the lifeline between mama and baby. 

In keeping with this strangeness, here are a few little-known and quirky facts about the squishy, squiggly vessel.

AVA

Umbilical cords 101: They contain two arteries and one vein, which is easily recalled with the acronym, and popular girls' name, AVA. The one, hefty vein brings oxygen and nutrient-rich blood to the fetus while the two skinnier arteries carry oxygen-poor and waste products back to mom's organs for filtering and re-oxygenating.  

An "elite" 1% of all umbilical cords contain only one of these arteries, which has a few interesting associations. First, 15-20-percent of single-artery umbilical cord babies also have cardiovascular abnormalities. Whether this association is the result of environment--the environment of decreased outflow of oxygen-poor blood, for instance--or as the part of some "genetic bundle" which includes both abnormalities is unclear. In addition, one investigator has shown an association between a single umbilical artery and maternal smoking during pregnancy. 

Yet another nail in ole tobacco's coffin. 

Pick a hand, any hand.

A detail of umbilical cords which can be recognized even by the least scientifically trained of on-lookers is its twisted appearance. The two arteries and one vein aren't paying tribute to candy canes or barbershop twisty things. Instead, these swirls are the result of fetal movement, but do they correlate with handedness? 

According to the folks who actually thought to study this, approximately 85-percent of umbilical cords are left twisted, leaving 15-percent twisted to the right, which is pretty much exactly the proportions of the population who are left and right handed: 85-percent of us are right-handed versus 15-percent who favor their left. 

I see your cord is as big as mine.

Speaking of fetal movement, it is greatly affected by the length of the umbilical cord, which may have something to do with behavior as the child ages. In a study which examined 35,799 umbilical cords, it was found that decreased cord length was correlated with decreased IQ and a greater incidence of motor abnormalities compared with very long cords which were associated with abnormal behavioral control and hyperactivity. 

I know, I know. You've been waiting your entire life to know umbilical cord facts such as these. You're welcome.