I miscarried twins at almost 23 weeks and was diagnosed with incompetent cervix. How hard is it to diagnose this? What would the treatment and risks be? How can I prevent this from happening again, and how long should I wait before trying again?

--Y.C.

In incompetent cervix, the cervix opens before pregnancy is complete, without contractions. This usually happens because of in inborn weakness of the cervical muscles, but it may also be due to previous surgery on your cervix -- such as LEEP or conization, which are sometimes used as treatments after abnormal Pap smears.

Incompetent cervix is usually diagnosed by careful review of the history surrounding your loss. Your physician may order an X-ray of your uterus to help diagnose this condition. Alternatively, he or she may notice that your cervix appears open and that a dilator (a narrow metal rod) easily passes through the cervix. If your physician is unsure of the diagnosis, weekly ultrasounds can enable him or her to monitor the shape and length of your cervix in order to pick up changes before they place your pregnancy at risk.

If your physician determines that you have this condition, then usually at about 12-14 weeks during your next pregnancy, a simple surgical procedure is done to stitch the cervix shut. You may choose general or regional (epidural) anesthesia. Often you will stay overnight in the hospital, and if everything looks okay, you will go home the next day. This procedure is successful in most cases. When your physician determines that you are ready to deliver, the stitch will be snipped during a routine pelvic exam. You may be allowed to go into labor, or your labor may be induced. If your bag of waters ruptures before your due date, you need to immediately call your doctor so the stitch can be removed.