The pathophysiology of infertility refers to the physiological processes that can lead to an inability to get pregnant or carry a pregnancy to term. Infertility can be caused by problems with the reproductive system in either the male or female partner. In women, infertility can be caused by problems with ovulation, blockages in the fallopian tubes, endometriosis, polycystic ovary syndrome, or problems with the uterus. In men, infertility can be caused by problems with the production of sperm, blockages in the reproductive tract, or problems with ejaculation.