There are many reasons for failure to prepare for pregnancy, which are mainly categorized into female infertility, male infertility, and other factors. 1. Female factors: female infertility may be related to tubal incompatibility, ovulation abnormalities or polycystic ovary syndrome, hyperthyroidism and other endocrine disorders caused by the disease, in addition to endometrial damage or uterine ovary organic lesions, will also affect the female pregnancy. It is necessary to combine ultrasound, hormone six, fallopian tube and ovulation examination and other items to clarify the cause and then treat the symptoms. 2. Male factors: unsuccessful pregnancy preparation may also be caused by male factors, such as poor sperm quality, dead sperm, oligospermia, hypospermia or sperm teratogenicity and other factors, which will also affect the chances of success. Men need to improve the semen routine and other detailed examination and treatment. 3. Other factors: If both husband and wife have no problems in the examination, the unsuccessful preparation for pregnancy is likely to be caused by prolonged emotional instability, excessive stress, staying up all night or smoking and alcohol abuse and other bad habits. Need to relax, change the bad habits, can also increase the chances of successful fertilization.