Semen analysis is an important basis for evaluating male fertility, and abnormal results suggest the presence of reduced fertility. The semen parameters most closely related to fertility are sperm count and motility, and sperm morphology is an important reference for predicting the success of in vitro fertilization-embryo transfer (IVF-ET). Most pregnancies can be achieved through consensual intercourse if the total number of motile sperm is greater than or equal to 40 million; IUI can be considered for pregnancies between 5 and 40 million; and IVF should be pursued at the earliest possible time for those with greater than zero and less than 5 million. Age and Fertility of the Woman: The fertility of a woman at 35 years of age is only about 50% of that at 25 years of age, decreasing to 25% at 38 years of age, and may further decrease to less than 5% over 40 years of age. In assisted reproduction, the age of the woman is the most significant factor affecting the success rate.