Conception is a complex physiological process that requires the following conditions: the ovaries discharge normal eggs; the semen is normal and has normal sperm; the egg and sperm are able to meet in the fallopian tube and unite to form a fertilized egg, which is successfully transported into the uterine cavity; and the uterine lining is sufficiently prepared for the fertilized egg to implant. A malfunction in any one of these components can prevent conception. Factors that prevent conception may be on the female side, on the male side or on both sexes. 1. Female infertility factors 1. Ovulation disorders: various factors cause ovarian dysfunction resulting in anovulation. (1) Central influence: dysfunction of the hypothalamic-pituitary-ovarian axis, causing menstrual disorders, such as anovulatory menstruation and amenorrhea; pituitary tumors causing ovarian dysfunction and infertility; mental factors such as excessive stress and anxiety on the hypothalamic-pituitary-ovarian axis. -(2) Systemic diseases: serious illnesses such as anovulation, menstruation, amenorrhea, etc. (2) Systemic diseases: severe malnutrition, excessive obesity or lack of certain vitamins in the diet, especially E, A and B, can affect ovarian function; endocrine metabolic diseases such as hyper- or hypothyroidism, hyper- or hypoadrenocorticism and severe diabetes mellitus can also affect ovarian function and lead to infertility. (3) Local ovarian factors: congenital ovarian hypoplasia, polycystic ovary syndrome, premature ovarian failure, functional ovarian tumors such as granulosa-follicular membrane cell tumors and testicularoblastoma can affect ovarian ovulation; ovarian endometriosis not only destroys ovarian tissues, but also causes severe adhesions and leads to infertility. Sometimes, although the lumen of the fallopian tube is open, the endometrium is damaged by inflammation and the tube wall becomes stiff, causing the loss of cilia movement and peristaltic function of the endometrium, which also affects the meeting and transport of sperm and eggs and causes infertility; endometriosis causes tubal adhesion and distortion or scar contracture, which restricts its movement and affects the picking up of eggs by the umbilical end. The endometriosis causes distortion or scarring of the fallopian tubes, which restricts their movement and affects the picking of eggs at the umbrella end, resulting in infertility. 3, uterine factors: uterine dysplasia, endometrial tuberculosis, uterine cavity adhesions, endometrial polyps, submucosal fibroids, ovarian luteal dysfunction, insufficient progesterone secretion, endometrial secretion response, etc., all affect the fertilization of eggs. 4, cervical factors: normal ovulation cervical mucus increased, clear and transparent, conducive to sperm through. In chronic cervicitis, the cervical mucus becomes sticky and contains a large number of white blood cells, which is not conducive to the movement of sperm and can affect conception; cervical polyps and cervical fibroids can block the cervical canal and affect the passage of sperm, and the narrowing of the cervical opening can also cause infertility. 5. Vulvar and vaginal factors: congenital abnormalities such as hymenal atresia, vaginal transverse septum, congenital absence of vagina and other congenital abnormalities prevent sexual life; in case of severe vaginal inflammation, a large number of white blood cells consume the energy material present in semen, reducing sperm motility and shortening its survival time and affecting conception. Second, the male factor: about 30% 1, abnormal semen: such as no sperm, reduced sperm count, reduced motility, abnormal morphology. 2. Obstruction of sperm transport: tuberculosis of epididymis and vas deferens can block the vas deferens and prevent sperm from passing; impotence and premature ejaculation often prevent sperm from entering the vagina. 3, immune function: sperm and sperm plasma can produce antibodies against their own sperm in the body and cause male infertility, and the ejaculated sperm can not pass through the cervical mucus because of their own agglutination. Factors of both sexes: 1. lack of knowledge about sex life; 2. mental tension caused by excessive anxiety about infertility of both spouses; 3. immune factors. Semen contains a variety of proteins, which can be used as antigens, mainly in the female reproductive tract, mainly in the cervical epithelium after absorption, resulting in an immune response, followed by the production of antibodies in the blood of the woman or local reproductive tract, such antibodies have agglutination or braking effect on sperm, which adversely affects sperm during sexual intercourse. In about 15-20% of infertile couples, anti-sperm antibodies are found in the serum or cervical mucus of these women by immunological examination, and these infertile couples, after using condoms for a period of time, can make the antibodies disappear and result in pregnancy.