What is cervical cerclage?
Cervical cerclage is a surgical procedure in which sutures are placed around the opening of the cervical canal. This is done to prevent premature loss of the fetus because of an opening or incompetence of the cervix. This procedure can be done through two different approaches either through the abdomen (transabdominal cervical cerclage) or through the vagina (transvaginal cervical cerclage). The sutures that are placed are then removed from the cervical region after completion of full term (37th weeks), although it can be removed earlier depending upon the circumstances. The main indication for this operation is when the mother is at risk of having the cervical canal opened early before the baby fully develops. However this operation is not suitable for every case of premature cervical opening and may be associated with serious complications.
Reasons for Cervical Cerclage
With progression of pregnancy the cervix gradually softens up with loss of the length of the canal (effacement) and dilation of the opening for facilitating the passage of baby through the canal. In mothers with incompetent or prematurely opened cervix the baby is likely to be delivered before complete maturation and before achieving maturity for independent survival.
The cervical ceclage procedure is recommended under the following circumstances:
- when there is history of three or more miscarriages in the second trimester with no such definite identifiable cause,
- presence of a short cervix as seen by ultrasound examination before 24 weeks of pregnancy especially seen in women with past history of cervical injury,
- premature birth or in cases where the length of the cervix is gradually reducing in spite of treatment,
- presence of cervical dilation with amniotic sac visible through it before 24 weeks (emergency cervical ceclage operation may be required).
Sometimes the cerclage procedure may be recommended before conception in women with repeated miscarriages without any identifiable cause.
Cervical cerclage is not appropriate in certain pregnant women like:
- vaginal bleeding during pregnancy,
- premature onset of labor pain,
- infection inside the uterus,
- premature rupture of the amniotic sac surrounding the baby,
- presence of multiple babies (twins, triplets), and/or
- known fetal abnormalities which the increases the risk of miscarriage.
Before the procedure, an ultrasound examination, cervical swab and even amniocentesis may be performed to:
- exclude the possibility of an infection,
- check the vital signs of the baby, and
- rule out fetal abnormality.
Usually the cervical cerclage is performed within the first 12 to 16 weeks of pregnancy and under emergency circumstances it can be performed up to 24. If there is a prolapsed fetal membrane then it should be appropriately managed before performing a cervical cerclage.
The procedure is done on an outpatient basis under general or local anesthesia. Cervical cerclage is done through the vaginal opening guided by ultrasound or through incision made on the abdomen and by lifting the uterus gently. Ultrasound examination is done after the procedure. The patient is allowed to go home provided that she has fully recovered from the effects of the anesthesia. The sutures are removed around the 37th week of pregnancy to facilitate vaginal delivery. In case of a C-section the suture might be kept in place until after the birth of the baby.