Recurrent abortion is defined as a person who suffers 2 or more consecutive fetal (weight ≤ 500 g) losses before 20 weeks of gestation with the same sexual partner. Its incidence has been reported worldwide to be 2% to 4%. The causes of recurrent miscarriage are extremely complex and there is a lack of accepted uniform screening guidelines, but a number of high-risk factors have been considered relatively well established, such as chromosomal abnormalities in both partners, anomalies in uterine anatomy, reproductive immune disorders, endocrine abnormalities, infections and pre-thrombotic states. In the past, recurrent miscarriages were called unexplained miscarriages and the treatment outcome was very unsatisfactory. Recently, with the development of reproductive immunology, a breakthrough has been achieved in the diagnosis and treatment of recurrent miscarriage, and the greatest contribution is made by “immunotherapy”. Although there are different reports on the efficacy of active immunotherapy in domestic and international literature (70%-90% success rate of fetal preservation), the multicenter large sample reports show its significant efficacy. Immunotherapy is active immunotherapy, mainly using lymphocytes from the husband or unrelated individuals as immunogen, stimulating the body to produce immune response and inducing the production of protective antibodies through intradermal injection. Indications: (1) 2 or more miscarriages; (2) normal karyotype analysis of the couple; (3) normal karyotype analysis of the embryo; (4) no abnormalities in the patient by systemic examination, which includes: no anatomical abnormalities of the reproductive tract; normal endocrine examination; negative autoantibodies; (5) negative closed antibodies. The specific procedure is as follows: aseptically draw 30ml of venous blood from the husband or a healthy third party, anticoagulate with an appropriate amount of heparin, make a suspension of lymphocytes so that the cell concentration reaches (20-40)×106/ml, inject subcutaneously into the lateral forearm of all patients, generally divided into 6-8 spots, observe the local reaction after 30 minutes, and if local reactions such as redness, blisters and hematoma appear, ice, anti-allergy, and Prevent infection and other treatment. If there is no positive change, the second course of immunotherapy will be started (however, due to the existence of individual differences, it is not excluded that some individuals continue not to change). If the pregnancy is positive, the pregnant woman will be advised to become pregnant within 3 months and come to the clinic as soon as the pregnancy is detected, and blood will be drawn to check the hormones and decide on the plan to preserve the pregnancy according to the specific situation, and to provide intensive treatment during pregnancy; if the pregnancy does not occur within 3 months, intensive immunotherapy will be given once a month until pregnancy. The incidence of recurrent miscarriage is on the rise, and although the exact cause is not yet completely clear and cannot be prevented at an early stage, it is recommended that certain factors that can cause recurrent miscarriage be detected early and treated promptly. When pregnancy is detected, it is important to visit the doctor and have blood tests for hormones to detect problems early and intervene in time. Although some of the current diagnostic and therapeutic methods for high-risk factors for miscarriage do greatly improve the pregnancy success rate in this group of patients, due to the limitations of medicine itself, there are still 10-20% of patients. We would like to suggest that patients with recurrent miscarriage should be seen early and treated promptly.