A pregnancy that is less than 28, or a fetus that weighs less than 1000g and is terminated, is called a miscarriage. There is a 20% chance of spontaneous abortion in normal couples, so couples who have only a history of spontaneous abortion need not be nervous, but can rest for 6 months and prepare for pregnancy after a good preconception health check. It is better to have an early checkup if you are pregnant and to keep the pregnancy if necessary. Three or more consecutive spontaneous miscarriages are called habitual miscarriages, and two consecutive spontaneous miscarriages are called recurrent miscarriages. In general, it is recommended that both spontaneous miscarriages for 2 times should be examined for the cause and treated for the cause to avoid another miscarriage. There are many factors that cause spontaneous abortion, including anatomical factors, endocrine factors, genetic factors, infectious factors and immunological factors. Other factors include male factor, maternal co-morbidities, poor living habits and environmental factors. There are also some cases of unexplained recurrent miscarriage that cannot be detected by current medical methods. Screening for the causes of spontaneous miscarriage includes the following: 1. anatomical abnormalities of the reproductive tract: ultrasound, hysterosalpingography or hysteroscopy to exclude endometrial polyps, submucosal fibroids, saddle-shaped uterus, longitudinal uterus, and double uterus; 2. endocrine examination: sex hormone 6, luteal progesterone, thyroid function, oral glucose tolerance and insulin release test; 3. chromosome examination: karyotype of both spouses, chromosome examination of the miscarried embryo, and chromosome examination of the miscarried embryo. 4.Infection factor examination: virus (toxoplasmosis, rubella, herpes) examination, cervical chlamydia, gonococcal examination; 5.Immunity factor examination: blood group of both spouses (ABO and RH blood group), reproductive immune antibody (anti-endometrial antibody, anti-cardiolipin antibody, anti-sperm antibody, etc.), closed antibody, etc.; 6.Semen routine and malformation rate examination of male partner. Repeated miscarriage couples through a comprehensive examination of the causes of miscarriage, if a clear cause is found, the majority of couples can succeed in pregnancy after treatment for the cause. 3, no treatment for chromosomal abnormalities, if necessary, genetic diagnosis of pre-implantation embryos; 4, spontaneous abortion caused by infection can be treated with drugs or according to drug sensitivity test, and then prepare for pregnancy after the infection factor turns negative; 5, spontaneous abortion caused by anti-sperm antibodies can be treated with glucocorticoids such as dexamethasone, prednisone for 1-3 months, while condom contraception You can try to conceive after the anti-sperm antibodies have turned negative. You can also choose artificial insemination treatment, where the sperm is washed and optimized for direct injection into the uterine cavity, which can exclude the interference of antisperm antibodies. Spontaneous abortion caused by anti-cardiolipin antibodies can be treated with aspirin – anti-platelet coagulation drugs for 1-3 months, and try to conceive after the anti-cardiolipin antibodies have turned negative. Low-molecular heparin therapy is an option if necessary. For patients with negative blocking antibodies, lymphocyte immunotherapy is feasible; 6. For male partner with abnormal semen, pregnancy can be achieved after normalization of all indicators by drug treatment or artificial insemination for pregnancy. The process of lymphocyte immunotherapy is relatively simple and safe. Generally, 30-50ml of the husband’s blood is taken and the lymphocytes (i.e. immune cells) are extracted and injected under the skin of the wife’s forearm. Lymphocyte immunotherapy can be done with the blood of an unrelated man who is not related to the wife if the husband has a blood-borne disease or other reason. Before treatment, both partners need to be tested for infectious diseases and eat a light diet for 1-2 days before the blood is drawn, avoiding overly oily foods. The treatment should be done at a time that avoids the woman’s menstrual period. Before trying to conceive, it is recommended to do 2-3 immunotherapy sessions with an interval of 3-4 weeks each time, and wait for the closed antibody to turn positive before getting pregnant, and then consolidate 2-3 sessions after pregnancy. If conception does not occur after six months, it is recommended to try for pregnancy after immunotherapy again.