Management of Incompetent Cervix
The cervix is the lowest part of the uterus and normally remains closed until the third trimester. Sometimes the cervix can prematurely dilate without pain or uterine contractions as a result of weakness of the cervix, which then opens under the growing pressure of the uterus. If this happens before 24 weeks (~6 months) it is generally referred to as Cervical Incompetence. Dilatation of the cervix occurring after 24 weeks is generally considered to be due to preterm labor and is associated with painful contractions.
What Are the Risks associated with Incompetent Cervix?
A weak cervix that starts to dilate under the pressure of the increased weight of the growing uterus can result in rupture of the membranes and cause leaking of amniotic fluid, which then results in preterm delivery of a baby that may be too premature to survive or who survives but has many problems associated with prematurity.
What causes Cervical Incompetence?
A cervix can be weakened as a result ofmultiple D&C's (either for miscarriages or abortions), damage to the cervix from a previous cone biopsy or LEEP procedure, a second trimester induction of labor or D&E, a birth defect of the mother causing an abnormal cervix , or unknown reasons.
How is the Diagnosis of Cervical Incompetence made?
The diagnosis of cervical incompetence is usually based on historical factors such as a prior pregnancy complicated by premature dilation in the second trimester followed by a loss of the pregnancy, or even a history of premature leaking of the membranes before 34 weeks. The diagnosis is confirmed by documenting changes sonographically (Vaginal Ultrasound), and/or clinically on pelvic examination.
What is the Treatment for Cervical Incompetence?
Women with cervical dilation prior to 24 weeks may be able to prevent a second trimester pregnancy loss by frequent sonographic evaluation of the cervix and placement of a cerclage if needed. Cerclage is a procedure on the cervix that essentially closes the cervix by sewing it shut and provides additional support to prevent premature cervical dilation. It is usually placed between 12 and 14 weeks in women with a history of Incompetent Cervix, but is also placed in emergency situations when cervical change has begun to occur. The stitch or cerclage is then removed before delivery. Sonographic evaluation by a Maternal Fetal Medicine Specialist is essential to prevent misdiagnosis. Sonograms to evaluate the cervix in women at risk of Incompetent Cervix start around 14 weeks and continue every two weeks until about 24 weeks.
What are the Risks of Cerclage?
All surgical procedures carry some risks and this applies to cerclage as well. The risks include infection of the cervix or membranes, premature rupture of the membranes, injury to the cervix or bladder, bleeding or tearing of the cervix, in addition to anesthesia risks.