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Dr. Christopher S. Baird

How did doctors create my belly button?

Category: Biology      Published: October 30, 2013

By: Christopher S. Baird, author of The Top 50 Science Questions with Surprising Answers and Associate Professor of Physics at West Texas A&M University

newborn baby
Public Domain Image, source: Christopher S. Baird.

Doctors did not create your belly button (or navel). The navel is not the scar or knot left by a doctor that cut your umbilical cord at birth. This fact is obvious to anyone that has ever had children or bathed newborns, but it is sometimes misunderstood by others. While you were in your mother's womb, your umbilical cord attached to your navel at one end and to your placenta at the other end. The placenta is a pancake-shaped mass of blood vessels that attaches to the wall of the mother's uterus. Food that your mother ate and oxygen that she breathed went into her blood, and then was carried to her uterus. Where your placenta and your mother's uterus touched, the food and oxygen was exchanged from your mother's blood to your blood. Your blood than carried the nutrients from the placenta, down the umbilical cord, through your navel, and into your body.

Once you were born, you no longer needed to get food and oxygen through your navel, as you could now get them through your mouth. As a result, the umbilical cord was no longer needed and your body had a natural way of getting rid of the cord. On its own, your body closed up the point where the umbilical cord joined your body and formed your belly button. When the doctor or midwife that assisted during your birth cut your umbilical cord, he or she cut it several millimeters away from the end of the cord, leaving a piece of the cord still hanging off your belly. He or she did this to let the body form a well-shaped belly button on its own. The remaining peice of umbilical cord is called a stump. A few days to weeks after your birth, when your body had formed a properly closed bell button, the stump fell off naturally like a scab falling off of a healed wound (assuming you did not have abnormalities at birth). The Mayo Clinic Guide to Your Baby's First Year states,

After your newborn's umbilical cord is cut, all that remains is a small stump. In most cases, the remaining cord will dry up and fall off one to three weeks after birth. Until then, you want to keep the area as clean and dry as possible. It's a good idea to give sponge baths rather than full baths until the cord falls off and the navel area heals...Exposing the cord to air and allowing it to dry at its base will hasten its separation. To prevent irritation and keep the navel area dry, fold the baby's diaper below the stump. In warm weather, dress a newborn in just a diaper and T-shirt to let air circulate and help the drying process.

Topics: baby, belly button, birth, navel, stump, umbilical cord