The cervix is located at the juncture of the vagina and the uterus and it contains cervical glands that produce mucus to support the sperms transit and provide nourishment. If the uterus is a “bottle”, the cervix is the neck, allowing sperm to enter, and eventually for a baby to exit.
When the mucus is insufficient, “too thick,” or contains antisperm antibodies, it can impede, or “kill” the sperm. When this occurs very few sperm will reach the egg(s) and fertilization is unlikely.
The cervical mucus may contain antisperm antibodies that can incapacitate or “kill “sperm. Antibodies are produced by the body in response to invading pathogens such as virus or bacteria. The immune system produces these antibodies to target the “invaders” as a first line defense against disease.
Sometimes the immune system mistakenly identifies sperm as an invading pathogen and seeks to destroy them. Numerous “dead” or immobile sperm in the cervical mucus is an indication of the presence of antisperm antibodies. The post coital test is sometimes used to measure sperm quality/quantity after intercourse. The couple has intercourse at home and the patient comes to our office where a sample of her cervical mucus is examined under the microscope.
Fortunately, cervical mucus problems can usually be treated successfully using intrauterine insemination (IUI). In IUI, a catheter is used to place washed and concentrated sperm directly into the uterus thus avoiding cervical mucus “problems”. “Unwashed” sperm must never be used in IUI as severe, or even fatal, allergic or inflammatory reactions can result.
Often IUI is augmented by the administration of follicle stimulating hormone (FSH) and is known as stimulated IUI. FSH causes the recruitment and development of several follicles, each of which contains an egg. Once the eggs mature an injection of hCG or LH is given to cause multiple ovulations and the insemination is timed. Stimulated IUI should only be performed by a trained infertility specialist due to potential medication side effects and the increased incidence of multiple births.