When a child swallows a safety pin, where does it end up?

Hopefully pin closed. Hopefully the safety pin was "closed" when swallowed, because it will end up in the child's gastrointestinal tract. It would be best to consult a physician or surgeon to see whether the pin needs to be removed surgically, or whether it can be allowed to pass with the child's stool. Please go to your nearest urgent care or emergency room.