Heartburn in pregnant women at night is caused by excessive secretion of gastric acid in the stomach, abnormal gastric emptying of pregnant women, and gastroesophageal reflux. The elevated HCG level in the body after pregnancy causes symptoms of loss of appetite, nausea and vomiting in pregnant women. The elevated progesterone prolongs the gastric emptying time, resulting in increased secretion of gastric acid. As the number of weeks of pregnancy increases, the uterus enlarges and compresses the fundus of the stomach, making the position of the stomach become horizontal, gastric emptying is obstructed, and gastric secretions irritate the gastric mucosa causing heartburn. Pregnant women are advised to eat less and more meals, eat light and easily digestible food, do not eat too sweet or spicy and stimulating food, and be active to reduce the symptoms.