A person who has a normal sexual life and has not had a pregnancy for one year without contraception is said to be infertile. Those who have never had a pregnancy without contraception are called primary infertility; those who have had a pregnancy and then have been infertile for one year without contraception are called secondary infertility. The incidence of infertility varies by country, ethnicity and region. In recent years, the incidence of infertility has been on the rise, and the results of a survey conducted by the World Health Organization in 33 centers in 25 countries in the mid-to-late 1980s showed that about 5% to 8% of couples in developed countries were affected by infertility, and the prevalence of infertility in some areas of developing countries could be as high as 30%, and about 6% to 15% in China. The number of infertility patients worldwide is about 80 to 110 million. The increasing trend of infertility prevalence may be related to late marriage and late childbirth, abortion, sexually transmitted diseases, stressful life, and irregular work and rest. Repeated abortions and ectopic pregnancies without obtaining a live baby are now covered by infertility. There are many causes of infertility, and the infertility factor may be in the female partner, male partner, or both sexes. Female factors account for about 40%, male factors account for 30% to 40%, and male and female factors account for 10% to 20%. 1. Female infertility factors Ovulation disorders and tubal factors are the most common factors. (1) Ovulation disorder: 25%-30%. Ovulation dysfunction leads to non-ovulation, or although ovulation occurs, the corpus luteum does not function well after ovulation. The main causes are: ① Hypothalamic-pituitary-ovarian axis dysfunction, including organic lesions or dysfunction of hypothalamus and pituitary gland. (2) Ovarian pathology, such as congenital ovarian dysplasia, polycystic ovary syndrome, premature ovarian failure, functional ovarian tumors, ovarian insensitivity syndrome, etc. (3) Abnormal adrenal and thyroid function can also affect ovarian function. (2) Tubal factors: Tubal obstruction or tubal incompetence accounts for about 1/2 of female infertility factors. chronic tubal inflammation (Neisseria gonorrhoeae, Mycobacterium tuberculosis, Chlamydia trachomatis, etc.) causing umbilical atresia or destruction of tubal mucosa can cause complete tubal obstruction leading to infertility. In addition, tubal insufficiency, long or narrow fallopian tubes, sequelae of pelvic inflammatory diseases and endometriosis can also lead to tubal infertility. (3) Uterine factors: uterine malformation, submucosal fibroids, endometritis, endometrial tuberculosis, endometrial polyps, uterine adhesions, etc. can affect the fertilization of eggs and lead to infertility. (4) Cervical factors: abnormal secretion of cervical mucus, cervical inflammation and abnormal immune environment of cervical mucus can affect the passage of sperm, which can cause infertility. (5) Vaginal factors: abnormal vulvovaginal development, vulvovaginitis and vulvovaginal scar can cause infertility. 2. Male infertility factors are mainly sperm production and sperm transmission disorders. (1) Semen abnormalities: normal sexual function, congenital or acquired causes of semen abnormalities, manifested as azoospermia, weak sperm, oligospermia, stagnant sperm development, teratospermia or incomplete liquefaction of semen, etc. (2) Sexual function abnormalities: dysplasia of external genitalia or erectile dysfunction, premature ejaculation, non-ejaculation, retrograde ejaculation, etc., so that sperm cannot be ejaculated normally into the vagina, can cause male infertility. (3) immune factors: under the condition that the immune barrier in the male reproductive tract is destroyed, sperm and sperm plasma produce anti-sperm antibodies (AsAb) in the body, so that the ejaculated sperm produce cohesion and cannot cross the cervical mucus. 3, both men and women factors (1) lack of basic knowledge of sexual life, sexual life can not or abnormal. (2) Both men and women look forward to pregnancy caused by excessive mental tension. (3) Immunological factors: ① Homoimmunity: sperm, sperm plasma or fertilized egg antigenic material enters the circulation through the destroyed natural barrier, generating antibodies so that the sperm and egg cannot combine or the fertilized egg cannot be laid. (2) Autoimmunity: the presence of multiple autoantibodies in the serum of some infertile women that may prevent the sperm from binding to the egg and affect conception. (4) Unexplained infertility: the cause of infertility cannot be confirmed by clinical system examination.