The mouth is the first stop in the body’s gastrointestinal (GI) tract, which also includes the esophagus, stomach, small and large intestines, and the rectum. When you swallow anything—food, drink, or a foreign (non-food) object—it travels through the GI tract, or gut.
When a foreign object is swallowed, it can get stuck in the esophagus, a small, soft tube that runs from the mouth to the stomach. The esophagus has thin, very flexible walls that can easily catch and bind hard objects that are trying to pass. The walls of the esophagus are so flexible that when it is empty, it collapses almost flat, like a fire hose with no water in it.
If a foreign body makes it past your esophagus, it has a pretty good chance of making it all the way through the GI tract.