Hiccups after spitting up are related to conditions such as catching a cold, indigestion, eating too much, and inhaling air. When babies are young, they are not well developed in all aspects and the autonomic nerves that regulate the diaphragm are not fully developed, so when they are stimulated, they will have hiccups. If the baby’s abdomen gets cold due to lack of attention to warmth, digestion and absorption will be affected, causing spasms in the gastrointestinal tract, resulting in pain in the baby’s abdomen, vomiting, and hiccups. If the baby has indigestion, the gastrointestinal tract cannot digest quickly after feeding, and it will also lead to abnormal peristalsis of the stomach, so the baby is also prone to vomiting and burping. In addition, the baby’s stomach volume is relatively small and horizontal when it is young, so if the baby eats too much milk or eats milk too fast, it may cause the baby to vomit and inhale more air if it eats milk too fast, so the baby also tends to show hiccups after vomiting.