If the first menstrual period after miscarriage is particularly heavy, it is common for the following clinical reasons: 1. caused by endocrine disorders, because after miscarriage, emotional and psychological changes will occur, endocrine changes will also occur, so there will be endocrine disorders, there may be excessive menstrual volume, but often with further physical recovery, menstruation will return to normal volume. 2. 2. Because there is a small amount of residue in the uterus after miscarriage that is not detected, the residual tissue flows out of the vagina together with the menstrual blood when menstruation occurs, resulting in an increase in menstrual volume, often accompanied by mild lower abdominal pain when menstruation occurs. This is a common clinical cause of heavy menstruation for the first time after miscarriage.