Tracheoesophageal fistula
Tracheoesophageal fistula is a connection between the esophagus and the trachea. The esophagus is the tube that connects the throat to the stomach. The trachea is the tube that connects the throat to the windpipe and lungs. Normally, the esophagus and trachea are two tubes that are not connected. This problem is also called TE fistula or TEF. It can happen in one or more places.
TE fistula is a birth defect. This means it's a problem you are born with. It happened when your baby was forming during pregnancy.
When a baby with a TE fistula swallows, liquid can pass through the connection between the esophagus and trachea. When this happens, liquid gets into your baby's lungs. This can cause pneumonia and other problems.
Esophageal atresia
TE fistula often happens with another birth defect called esophageal atresia. This means your baby's esophagus doesn't form well during pregnancy. It forms in two parts instead of one. One part connects to the throat. The other part connects to the stomach. But the two parts don't connect to each other.
Since the esophagus is in two parts, liquid that your baby swallows doesn't pass as it should through the esophagus and reach the stomach. This means your baby can't digest milk or other fluids.