What is an incompetent cervix?
The cervix is the opening between the uterus and the vagina. The cervix changes slightly throughout every woman's menstrual cycle, and though it is closed, there is a tiny opening that allows menstrual blood and tissues to leave the body, and to allow semen in so you can get pregnant. During pregnancy, the cervix should remain closed to keep the baby, amniotic sac and fluid, and the placenta inside. As a pregnancy progresses, all these things put some pressure on the cervix.
An incompetent cervix, also called a weakened cervix, can't handle this pressure and will start to dilate (open) too early on in a pregnancy. This can result in a miscarriage or preterm labor if it isn't detected and treated. An incompetent cervix will manifest itself during the later stages of pregnancy, the second and third trimesters. An incompetent cervix is not an issue during the first trimester.
Around one in every 100 pregnancies will be affected by an in competent cervix. An incompetent cervix is usually caused by physical events surgery on the cervix, an abortion, D&C following a miscarriage, or damage sustained during childbirth. A cervix can also be malformed from birth, and exposure to DES, diethylstilbestrol, in the womb when your mother was pregnant with you may also be responsible for a weakened cervix. Women who have had several second trimester miscarriages or have gone into labor prematurely may have an incompetent cervix. Talk to your doctor if this applies to you. Around a quarter of second-trimester miscarriages is caused by an incompetent cervix, and being aware of the problem can potentially prevent another miscarriage with a subsequent pregnancy.
What symptoms will you experience if you have an incompetent cervix?
Miscarriage or labor may be the only physical symptom that a mom who suffers from an incompetent cervix has. Unfortunately, doctors don't screen for an incompetent cervix routinely. Many even hold that a woman would have to have two second-trimester miscarriages before looking into the state of her cervix seriously. Ultrasound can sometimes indicate an incompetent cervix, but not always. A physical examination (which could be a little risky and trigger bleeding or even contractions) during pregnancy is more revealing a cervix that is open, or dilated, is in trouble.
The most common treatment that "strengthens" an incompetent cervix and prevents miscarriage and early labor is a cerclage, which is very minor procedure essentially, a cerclage is a stitch in the cervix that will literally keep it shut. A cerclage is normally placed between weeks 14 and 16 of a pregnancy. Women who go into labor and already have contractions, a cervix dilated beyond 4 cm, or broken waters, can't be helped with a cervical cerclage.
Treatment for an incompetent cervix is, therefore, usually something that applies to the pregnancy you have after your incompetent cervix is diagnosed. A cervical cerclage is a very safe procedure, but there are small risks of uterine rupture and bladder rupture, as well as cervical damage if you go into labor while the stitch is in place. There is also a small chance of hemorrhage, meaning excessive blood loss. This is why a cerclage is removed after around 36 weeks, when going into labor would not result in a baby who is born very prematurely.
Your doctor may advise you to remain on bed rest, perhaps even in the hospital, in the final weeks after your cerclage is taken out. Progesterone cream may strengthen the cervix in some circumstances, and many women are advised to go on bed rest or modified best rest as a preventative measure.
You should talk to your doctor about your particular situation and what will be the best option in your case if you have been diagnosed with an incompetent cervix and fear that a cerclage is not enough to prevent preterm labor or pregnancy loss. I've also come across several news reports of women with a history of second trimester miscarriages due to an incompetent cervix lying "upside down" in hospitals beds for quite a long period during their pregnancy. This is done to take pressure off the cervix, and is apparently quite successful. Read mother spent three months upside down to avoid miscarriage for one example of how this treatment functions in practice.