The etiology of miscarriage is complex and uncertain. In domestic and international guidelines and consensus, most of the etiologies of miscarriage are summarized as: 1) genetic factors; 2) uterine structural factors; 3) endocrine factors; 4) immune factors; 5) thrombotic tendency; 6) infectious factors, etc. Because there are many reasons for recurrent miscarriage and embryonic arrest, there are many items to be examined and it will take about half a month. Please read the following procedures carefully and arrange your time to avoid futile road trips. 1.First consultation Bring all the examination information to the doctor. After taking a careful history, the doctor will do a gynecological double or triple consultation to check the routine white belt, mycoplasma and chlamydia. The following tests are also scheduled. 2. Fasting blood test for sex hormone 6 on day 2-4 of the cycle. (Blood is seen on the 1st day of the menstrual cycle). 3. 3-7 days after menstruation, do not have intercourse, do tubal hysterosalpingogram, or hysteroscopy with endometrial biopsy, or cervical exploration; gynecological examination, combined bacterial vaginosis test, chlamydia test, mycoplasma culture. (It is the doctor’s choice what to do for these items). 4.Day 9-4-12 of the cycle Gynecological ultrasound to look at the endometrium and ovarian follicles. 5.Cycle day 22-24 Fasting blood test for the following items: (1) routine blood; (2) blood type (ABO/Rh); (3) P (progesterone); (4) TORCH; (5) thyroid function 3 items; (6) fasting and 2 hours postprandial glucose; (7) fasting insulin level (optional); (8) lipids 4 items (optional); (9) chromosomes (optional); ( (10) 8 antibodies (including: anti-sperm antibodies, cardiolipin antibodies, endometrial antibodies, anti-ovarian antibodies, anti-nuclear antibodies, anti-HCG antibodies, anti-hyaline antibodies, anti-trophoblast antibodies); (11) 5 hepatitis B; (12) liver function; (13) renal function; (14) D2 aggregation; (15) maximum platelet aggregation rate; (16) homocysteine; (17) antithrombin activity (18) protein C activity, protein S activity; (19) blood rheology; (20) lupus anticoagulant; (21) ANA; (22) antithyroid antibodies; (23) ABO hemolysis (optional); (24) intraerythrocytic folate and VB12; (25) closed antibodies. 6.Basal body temperature measurement Basal body temperature is measured for one cycle (specific doctor’s guidance is needed) to see ovulation and luteal function. 7.Check the husband’s semen routine 3-5 days after the same party. Check husband’s chromosomes (optional), husband’s anti-sperm antibodies, husband’s sex hormone six items. Chromosomal examination of both husband and wife. If one of the couple is a reciprocal chromosome translocation or a Roche translocation carrier, the risk of fetal chromosomal abnormalities is higher, which may lead to infertility, recurrent spontaneous abortions, and the birth of a deformed child with low IQ. Some couples have chromosomal “abnormalities” that are actually polymorphic variants and are not pathological. The common ones are inter-arm inversion of chromosome 9, large Y chromosome, and increase of chromosome followers in D/G group. Some doctors may think that the occurrence of chorionic chromosome aneuploidy in spontaneous miscarriage is a random event, and since the miscarriage has already occurred, the examination of chorionic chromosome cannot change the outcome of this miscarriage, so why bother with it. The incidence of chorionic villus aneuploidy in spontaneous miscarriage is about 50%, and with the results of this test, at least half of the causes of this miscarriage can be answered. Without evidence of a chorionic chromosome test, doctors are often unable to answer questions about the cause of the miscarriage. If the chorionic villi chromosome is abnormal and occurs consecutively, it suggests an increased risk of miscarriage due to chromosomal abnormalities in the fetus in the next pregnancy, without much testing for other causes, and third generation in vitro fertilization (PGS) may be recommended if necessary; if the chorionic villi chromosome test is normal karyotype, indicating that the cause of this miscarriage is not chromosomally related, testing for other causes needs to be considered for attention.