1. IVF routine examination 1. Both spouses are jointly examined: blood type, blood routine, urine routine, biochemical examination, hepatitis B triple system, syphilis, HCV, HIV examination, cervical secretion/seminal fluid gonococcal culture, mycoplasma, chlamydia examination. 2.Female side examination: basic endocrine, anti-mullerian hormone, thyroid function, TORCH, cervical TCT, electrocardiogram, chest X-ray and breast ultrasound, etc. 3. Male side examination: endocrine, semen routine, sperm morphology, seminal plasma biochemistry, sperm DNA fragmentation, genital ultrasonography, etc. If abnormalities are found during the examination, consultation and treatment will be conducted in the corresponding department, and the treatment plan will be determined with the specific situation of the department. 1. Chromosomal examination: primary infertility, history of adverse pregnancy (spontaneous abortion, ectopic pregnancy and fetal abnormality), and those who intend to perform ICSI. 2. Hysteroscopy: (1) Hysteroscopy before IVF/ICSI or before transplantation for low menstrual flow, thin endometrium, suspicious adhesions in the uterine cavity, occupying lesions in the uterine cavity as indicated by ultrasound or iodine oil imaging, uterine malformation, ectopic pregnancy and history of repeated miscarriage; (2) Hysteroscopy as appropriate for one transplantation without pregnancy; (3) routine hysteroscopy for ≥ 2 transplantations without clinical pregnancy. (3) routine hysteroscopy for ≥ 2 transplants without clinical pregnancy. Treatment will be performed if abnormalities are found. Surgical removal of endometrial polyps, surgical removal of submucosal fibroids affecting the uterine cavity, hormone replacement for endometrial repair after adhesion separation, hysteroplasty for uterine malformation if necessary. 3.Laparoscopic surgery: for severe hydrocele or hydrocele with embryo transfer, laparoscopic tubal ligation or tubal resection should be performed before re-transfer. 4. Immunological examination: antiphospholipid antibody, closed antibody and hemolysis examination for recurrent miscarriage, recurrent biochemical pregnancy and recurrent transplantation failure.