Cervical Factor Infertility occurs when the cervical mucus is not the right consistency, does not contain the right nutrients, or contains antisperm antibodies. Any of these cervical abnormalities can prevent the sperm from swimming through and fertilizing the egg.
If the cervical mucus contains antisperm antibodies, the antibodies will attack the sperm as if they were bacteria or viruses and prevent them from swimming through. Usually, these antibodies are produced by the female immune system; rarely, however, a man can produce antibodies to his own sperm.
The first choice of treatment for Cervical Factor Infertility is intrauterine insemination (IUI), which places washed and concentrated sperm directly into the uterus, avoiding exposure to the cervical mucus.