The birth process places mechanical stress on a baby's head and cervical spine. Prolonged labor or assisted delivery, and positioning during birth, can leave residual tension in the upper neck. Because the nerves governing digestive function pass through this region, that tension can affect how the stomach and esophagus operate.
This connection is why Dr. Bronstein asks about the birth history during an infant reflux evaluation at Beacon Clinic of Chiropractic. The details of the delivery often point toward the origin of the structural tension that chiropractic care is designed to address.