Early pregnancy reaction after miscarriage usually disappears basically on the 2nd day. Early pregnancy reaction is due to the increase of human chorionic gonadotropin in blood, which leads to the decrease of gastric acid secretion, delay of gastric emptying and symptoms such as nausea, vomiting and loss of appetite. When human chorionic gonadotropin in blood was checked on the second day after miscarriage, it was found to be reduced by more than half. When human chorionic gonadotropin in blood is reduced, early pregnancy reaction will be reduced or even disappeared. In normal pregnancy, human chorionic gonadotropin in the blood increases exponentially every other day, and then remains stable and stops increasing at 8-10 weeks of pregnancy, and starts decreasing after a period of time, so generally, in normal pregnancy, early pregnancy reaction starts to decrease gradually after 12 weeks of pregnancy until the symptoms disappear.