Unsuccessful pregnancy may be caused by physiological factors of both parties, or it may be caused by certain diseases suffered by both men and women, which should be promptly consulted to identify the causes. 1. Physiological factors: Unsuccessful pregnancy may be related to age, nutrition, bad hobbies, mental stress and so on. The fertility of both men and women can gradually decline with age, and long-term severe malnutrition, anemia, or smoking, alcoholism, etc., can affect pregnancy. In addition, the lack of sexual knowledge of both husband and wife as well as high mental tension can also lead to unsuccessful pregnancy. 2. Pathological factors: (1) Male factors: male congenital developmental abnormalities, severe varicocele, etc., can cause semen abnormalities, low sperm count, reduced vitality and abnormal morphology, thus leading to unsuccessful pregnancy. Impotence, premature ejaculation, etc., which prevent sperm from entering the female vagina, or poor development of external genitalia, etc., can lead to unsuccessful pregnancy. (2) Female factors: abnormal ovarian development, polycystic ovary syndrome, inflammation of the fallopian tubes, endometrial abnormality, vaginal inflammation, cervical inflammation, etc. can lead to abnormal ovulation, which can lead to unsuccessful pregnancy. Couples who have been unsuccessful in getting pregnant for a long period of time should go to the reproductive department of the hospital in time to find out the reason for the failure of pregnancy and actively carry out the corresponding treatment.