When the baby is in the mother's uterus, it can't eat or breathe on its own, so it needs some help. The baby has a little tube that goes to its middle called the umbilical cord. The umbilical cord goes to the placenta, which connects to the mother's uterus.Here's how it works. First, the food that the mother eats and air that she breathes get into her bloodstream as very tiny pieces called molecules.These molecules, or tiny pieces of food and air, travel through the mother's bloodstream to her placenta. From there, they go to the umbilical cord and into the baby's body. That's how the baby eats and breathes inside the uterus.After a baby is born, the umbilical cord goes away. Guess what's left? Your belly button.Reviewed ByReview Date: 09/16/2008Dan Sacks MD, FACOG, Obstetrics & Gynecology in Private Practice, West Palm Beach, FL. Review provided by VeriMed Healthcare Network.