The constant gas after delivery may be caused by physiological reasons such as uterine contraction or pathological reasons such as indigestion, which need to be analyzed specifically. 1. Physiological reasons: in order to reduce bleeding after delivery, the uterus will be stimulated to make it contract constantly, and the uterus will stimulate the intestinal tract at the same time, increasing gastrointestinal peristalsis, resulting in the phenomenon of constant flatulence. 2. Pathological causes: If you eat more food that is easy to pass gas or difficult to digest after delivery, it may lead to indigestion, and the food residue will be fermented and gas-produced abnormally in the intestines, which will lead to a lot of gas passing. After miscarriage, you should pay attention to rest, eat a balanced diet and do not overeat. There may be other reasons why you keep passing gas after miscarriage, so it is recommended that you go to the hospital for examination to clarify the cause and then treat the symptoms.