Emergency Cervical Cerclage. Is There a Role for Amnioreduction?

Abstract

Cervical incompetence is a well recognized cause of recurrent mid-trimester pregnancy loss. Treatment of this condition is traditionally prophylactic cerclage either in the nonpregnant state or at 10 to 16 weeks' gestation (1). Under these ideal conditions, the fetal survival rate increases from approximately 20% before elective cerclage to 78437% after elective cervical cerclage (2,3). As no universally accepted diagnostic test exists for this functional entity it remains a diagnosis of exclusion and the decision to embark on cervical cerclage usually depends on the history of repeated pregnancy losses occurring in the second trimester. Other indications may include multiple terminations of pregnancy, deep conization of the cervix, cervical amputation, cervical laceration or congenital uterine anomalies. A policy of prophylactic cerclage results in many unnecessary procedures being performed (4) and accordingly some would advocate screening an at-risk population with weekly vaginal assessment of the cervix (5) or ultrasonographic assessment (6).Despite meticulous screening and surveillance, cervical incompetence may not be diagnosed until a patient presents with painless dilatation of the cervix and the fetal membranes protruding through the dilated 0s. Such a presentation is high risk for both the mother and fetus, demanding emergency management if the pregnancy is to be salvaged. Fetal survival rates of 48-68% have been reported after emergency cerclage (2). We present 3 such cases of emergency cervical cerclage assisted by amnioreduction which we believe may be a useful tool in some circumstances. CASE REPORTS Case 1A 34-year-old woman presented to her obstetrician for management of her fourth pregnancy at I5 weeks' gestation by dates. The pregnancy had been complicated by a threatened abortion at 6 weeks' I. Obstetric/Gynaecology Fellow.

Amnioreduction in Emergency Rescue Cervical Cerclage with Bulging Membranes

“…This surgical technique reinforces the cervical muscle by placing sutures above the opening of the cervix to narrow the cervical canal, usually done between 12-16 week of gestation or urgently later during second trimester. Under the ideal conditions, the fetal survival rate increases from 20% to 78-87% after elective cerclage (6,7). Without screeningand surveillance, cervical incompetence may not be diagnosed until patient presents with painless dilatation of the cervix and fetal membranes protruding through dilated cervix.…”

Does amnioreduction increase success of emergency cervical cerclage in cases with advanced cervical dilatation and protruding membranes?

“…Amnioreduction has been introduced for two main purposes in the literature: 1) to lower the pressure exerted upon the membranes and 2) to obtain amniotic sample for investigation of intra=amniotic infections [4][5][6][13][14][15]. In 1979, Goodlin introduced amniocentesis in cases with cervical incompetence [4].…”

Emergency Cerclage: Outcomes, Patient Selection, and Operative Considerations

“…Methods to put the cervix on traction have also been described; these include use of ring forceps or stay sutures to gently pull the cervix distally beyond the bulging sac. 42 A combination of these procedures is often utilized to optimize visualization and placement of the stitch. Amnioreduction has also been described in several small studies to reduce the hydrostatic forces exacerbating membrane prolapse through the dilated cervix.…”

“…Amnioreduction has also been described in several small studies to reduce the hydrostatic forces exacerbating membrane prolapse through the dilated cervix. 42,43 Postoperative Management…”