Conception is a complex physiological process that requires the following conditions: 1) the woman’s ovaries discharge normal eggs; 2) the semen is normal and contains normal sperm; 3) the egg and sperm can meet in the fallopian tube and unite to become a fertilized egg, which is transported smoothly into the uterine cavity; 4) the endometrium is suitable for the fertilized egg to settle; abnormalities in any of these parts can prevent conception and lead to infertility. Any of these components can prevent conception and lead to the occurrence of infertility. The factors that prevent conception may be in the female partner, in the male partner, or in both men and women.