Infertility is a serious reproductive health event among population problems. It is also a difficult condition involving multiple disciplines. After consultation, after the initial screening and diagnosis of infertile couples, the etiology is categorized into five major categories: 1, female ovulation disorders 2, pelvic pathology 3, male infertility 4, immune factors 5, and unexplained infertility. I. Comprehensive condition assessment for initial diagnosis: Routine collection of medical history and physical examination of infertile couples 1. General medical history, including marriage and childbearing history, menstrual history, past medical history, family history, treatment history, etc.; 2. Routine physical examination of the whole body, including height, body mass index, developmental and nutritional status, skin and limbs and other signs; 3. Comprehensive assessment of the psychological and mental status, social factors and living environment. The pathway of etiological screening: 1. Routine semen analysis of the male partner: the indicators were tested according to the standards of the fourth edition of the WHO. If the result is abnormal, the test should be repeated 2-3 times for confirmation. Secondary infertility also needs to be examined. 2. Female ovulation monitoring: (1) Basal body temperature measurement, usually at least two cycles; (2) Transvaginal ultrasound dynamic ovulation monitoring. If the cycle is regular, it usually starts on the 11th-12th day of the cycle, and a sinus follicle count (the number of sinus follicles on both sides of the ovary is totaled) is recorded for each monitoring cycle. Monitoring is scheduled according to the diameter of the follicle until ovulation; every 3 days if the follicle is 12 mm in diameter; every 2 days if the follicle is 14 mm in diameter; and daily if the follicle is 16 mm in diameter. The normal range of mature follicle diameter is φ18-25mm; if ovulation is abnormal, monitor for 2-3 consecutive cycles; after the follicle diameter reaches the standard, ultrasound can be used to determine ovulation 48 hours after the urine LH is elevated, or after the basal body temperature rises. (3) Hormone measurements are performed only in women with abnormal or anovulatory ovulation, bilateral ovarian sinus follicle counts < 6-8, and older women (> 35 years). (4) If necessary, a single progesterone measurement at mid-luteal phase (one week after ovulation) or histologic examination of the endometrium to determine the presence of ovulation. (3) Double and triple diagnostic examination of the pelvis: emphasize the gynecologist’s meticulous examination of the woman’s pelvis. Emphasis is placed on palpation of the texture and mobility of the uterus, as well as palpable nodules of the uterosacral ligament. For patients with positive signs, laparoscopy is recommended as appropriate for diagnosis. 4. Hysterosalpingography: Hysterosalpingography is recommended to use iodized oil as the contrast medium. Plain films of the abdomen are taken on the 2nd day of the imaging to analyze the morphology of the uterus and the patency and function of the fallopian tubes. Generally, the test is performed in patients who are generally normal in steps 1-3, or who have secondary infertility. 5. If no positive result is found in all four steps, the initial diagnosis is unexplained infertility. Third, the etiology of the initial screening path selection 1, the uncontraceptive less than one year, acute or subacute inflammation of the pelvis, age ≥ 40 years old, ovarian hypoplasia of patients, in principle, as far as possible not tubal imaging. 2, for primary infertility, young, infertile couples with relatively short years of infertility, the etiology of which is initially determined to be persistent anovulation, after the woman corrects her lifestyle and controls her weight, she can try to carry out 3-4 cycles of ovulation, and if she is infertile, she can then carry out uterine tubal iodine oil angiography. 3. For patients who are still diagnosed with azoospermia or severe oligozoospermia after repeating the first step of the initial screening, and the expected method of assisted conception is in vitro fertilization, tubal iodine-oil angiography can be avoided. 4, for pelvic double or triple diagnostic examination, suggesting that there are suspected endometriosis foci in the pelvis, or uterine tubal iodine oil angiography suggests pelvic adhesions, tubal communication but not smooth patients, it is recommended to carry out further diagnosis of laparoscopy. However, laparoscopic surgery is prudent for patients with reduced ovarian function to avoid further impact on ovarian function. 5.For patients with basal body temperature and ultrasound monitoring suggesting anovulation, further hormone measurements should be performed to determine the site and type of etiology.