What is an incompetent cervix?
A true incompetent cervix--one that is too weak to support the pregnancy and will never work normally--can often be successfully treated by stitching the cervix shut. This procedure is called cerclage. However, as a pathologist I see this diagnosis made too often. When I study tissues from pregnancies allegedly lost due to an incompetent cervix, I most commonly find that there is some other problem in the uterus which may have helped the cervix not do its job right and open too soon.
The cervix can soften when there is an acute subclinical infection, a chronic inflammation such as from "immune" problems, and a sick placenta due to blood vessel problems. Each of these processes can cause tissue injury, cell death, changes in hormone levels and inflammatory chemical imbalances that can send the wrong message to the cervix and cause a structurally competent cervix to behave "incompetently." Not surprisingly, cerclage often fails when the problem is not in the cervix's strength but elsewhere.
If you've been told your pregnancy loss was due to an incompetent cervix it's important to have your tissues or slides examined by a reproductive pathologist to identify what caused your cervix to open too soon. Treating the underlying problem would be the most effective way to prevent painless cervical dilatation in the future. However, your obstetrician may probably perform a cerclage prophylactically in your next pregnancy too. This may be wise since you'll want to make sure to avail yourself of all available forms of "insurance."
