Aunt that is menstruation, menstruation less than two or three days is considered to be related to endocrine disorders, a history of repeated uterine operations, etc. It is also necessary to further clarify whether this bleeding is menstruation or abnormal bleeding, the common causes of abnormal bleeding are pre-menstrual abortion, cervical or endocervical lesions or injuries to the reproductive tract. 1. Endocrine disorders: If the patient has recently had a stressful life and work, or has a combination of endocrine diseases such as polycystic ovary syndrome, premature ovarian failure, hypothyroidism, etc., due to the patient’s irregular ovulation or lack of ovulation, the endothelium is not transformed into secretory endothelium and can’t be completely stripped off, resulting in a small amount of menstruation. 2. History of repeated uterine operations: For women with a history of repeated uterine operations such as abortion, IUD removal and IUD insertion, the cervix and endometrium will be damaged to different degrees, resulting in poor endometrial hyperplasia or cervical adhesions, and so the patient will have a low menstrual flow or poor menstrual discharge. 3. Abnormal bleeding: If a woman has an intrauterine pregnancy with preeclampsia, cervical or endometrial lesions or damage to the reproductive tract may also lead to a small amount of bleeding, the patient thinks that menstruation, need to be further consultation to rule out abnormalities in order to ensure the health of the body. For patients with a small amount of vaginal bleeding, it is recommended to go to the gynecology department of a regular hospital, complete ultrasound, sex hormones and other related examinations, to clarify the cause of the disease under the guidance of the doctor active treatment.