Selective reduction in complicated monochorionic pregnancies: a systematic review and meta-analysis of different techniques

Objective This systematic review and meta-analysis aimed to compare the perinatal outcomes of complicated monochorionic pregnancies after selective reduction by radiofrequency ablation, bipolar cord coagulation, and interstitial laser. Data Sources We searched PubMed, Scopus, and Web of Science, from the inception of the database up to April 26, 2021. Study Eligibility Criteria Studies comparing at least 2 selective reduction techniques among complicated monochorionic pregnancies and presenting data on perinatal outcomes, including gestational age at procedure, gestational age at delivery, procedure to delivery interval, preterm premature rupture of membranes, preterm birth, survival rate, and birthweight, were eligible. Methods The random-effects model was used to pool the mean differences or odds ratios and corresponding 95% confidence intervals. Heterogeneity was assessed using the I2 value. Results A total of 10 studies with 734 cases of fetal reduction met the inclusion criteria, of which 9 studies with 674 fetuses were eligible for quantitative synthesis. In 8 studies that compared radiofrequency ablation with bipolar cord coagulation, radiofrequency ablation was associated with increased procedure to delivery interval (days) (mean difference, 13.42; 95% confidence interval, 1.90–24.94; P=.02; I2=0.0%), decreased preterm birth (odds ratio, 0.50; 95% confidence interval, 0.29–0.85; P=.01; I2=3.0%), and decreased preterm premature rupture of membranes (odds ratio, 0.45; 95% confidence interval, 0.27–0.73; P=.001; I2=0.0%). Radiofrequency ablation and bipolar cord coagulation had comparable survival rates (odds ratio, 0.85; 95% confidence interval, 0.54–1.35; P=.49; I2=0.0%). In 3 studies that compared radiofrequency ablation with interstitial laser, there was no significant difference in gestational age at delivery (P=.07) or survival (P=.15). In 3 studies that compared bipolar cord coagulation with interstitial laser, bipolar cord coagulation was associated with a higher survival rate (odds ratio, 3.21; 95% confidence interval, 1.13–9.10; P=.03; I2=0.0%), but the gestational age at delivery was comparable between groups (P=.16). Conclusion This study demonstrated that radiofrequency ablation has a greater procedure to delivery interval and decreased preterm premature rupture of membranes and preterm birth than bipolar cord coagulation. Although there was no difference in gestational age at delivery for either bipolar cord coagulation, radiofrequency ablation, or interstitial laser, survival was higher with bipolar cord coagulation than with interstitial laser.