Conclusion
The Shirodkar cerclage technique achieves greater cerclage height and longer interval between time at cerclage insertion to delivery, leading to increased birthweight and a reduction in PPROM and PTB when compared to the McDonald approach. By choosing the Shirodkar technique rather than the McDonald technique, one additional preterm birth would be prevented for every 38 cerclage procedures. Clinicians should consider these results when deciding which cerclage technique to utilise; however, further unbiased high-quality studies are needed to provide stronger supporting evidence that the Shirodkar approach has the potential to achieve better outcomes when compared to the McDonald approach. We recommend that obstetricians in training should be taught both surgical approaches where possible and decisions about which technique to use should be individualised to the woman.