Optimal surgical technique at cervical cerclage to prevent pregnancy loss, a systematic review

Abstract

Objective

Cervical cerclage has been used for decades for prevention of preterm birth; no consensus regarding optimal surgical technique exists. This review assesses if Shirodkar’s technique (bladder dissection) is superior to McDonald’s (without dissection) with respect to pregnancy loss and maternal-fetal outcomes. A secondary aim is to assess potential benefits of double cerclage.

Methods

Systematic review was conducted, PROSPERO protocol (CRD42023472563). MEDLINE, Embase, CINAHL and Cochrane Library were searched. 1647 abstracts were screened, 22 studies met inclusion criteria. Bias was assessed using ROBINS-I and ROB2 and meta-analysis conducted using RevMan.

Results

Odds of pregnancy loss and birth <37 weeks did not differ between dissection and no dissection groups (OR 0.95 [95 %CI 0.60–1.48], I²38%), (OR 0.86, [95 %CI 0.63–1.19], I²23%). Dissection prolonged pregnancy by 2 weeks (MD 2.29 [95 %CI 1.49–3.10], I²44%) and reduced birth <32 weeks, (OR 0.43 [95 %CI 0.19–0.61], I²0%). Double cerclage reduced pregnancy loss, (OR 0.52 [95 %CI 0.28–0.98], I²29%), and birth <28, <32, <34 weeks, however not at <37 weeks, (OR 0.96, [95 %CI 0.64–1.45] I²35%).

Conclusions

No difference in odds of pregnancy loss was evident between surgical techniques, however dissection was associated with prolongation of pregnancy by 2 weeks and reduced odds of birth <32 weeks. Double cerclage may provide additional benefits in prevention of preterm birth. Overall quality of evidence is low. Choice of technique should be informed by obstetric history, clinical examination, and clinician preference.