Fetal Outcomes and Prognostic Factors After Radiofrequency Ablation for the Selective Reduction in Complicated Monochorionic Multiple Pregnancies

Abstract

Rationale and objectives: Monochorionic pregnancies are responsible for some severe complications, and selective reduction of a single fetus can improve pregnancy outcomes. This study evaluated the fetal outcomes and procedure-related prognostic factors after radiofrequency ablation (RFA) in complicated monochorionic multiple pregnancies.

Materials and methods: This prospective cross-sectional study was conducted in an academic center from June 2020 to January 2022. The participants were 70 women with monochorionic multiple pregnancies who were candidates for selective fetal reduction by RFA. All participants' demographic data, RFA-related information, and pregnancy outcomes were evaluated and reported.

Results: The RFA procedure was successful in all participants. The most frequent RFA indications were twin-to-twin transfusion syndrome following selective intrauterine growth restriction. The mean gestational age at birth was 33.60 ± 5.62 weeks. Also, 11 (15.7%) of the cases had preterm delivery up to 30 days after RFA. The total pregnancy loss rate was 12 (17.14%), and the total fetal survival rate after RFA was 82.85%. The mean time of the RFA procedure was 130.8 ± 83.3 seconds. The procedure was conducted easily in 31 (44.2%) cases. Although the meantime of RFA procedure was longer in the not-easy group, the difference in surgery time was not significant (P = .296). There was no significant relationship (P = .623) between RFA indications and the gestational age of the remained fetus at delivery. The RFA needle was passed through the placenta in 18 (25.7%) cases. The mean gestational age at the delivery time was significantly lower in this group compared to their counterparts' gestational ages without needle placental passage (P = .030). Also, there was no significant correlation between gestational age at pregnancy termination and RFA cycles (P = .219).

Conclusion: RFA is a relatively safe and minimally invasive procedure for the selective reduction of complicated monochorionic fetuses. Although mortality, premature membrane rupture, and preterm delivery are the potential risk factors for the remaining co-twin. According to this study, gestational age at the time of the procedure and passing the needle through the placenta can affect the outcome. Other procedure-related factors like easy- or hard-access procedures, and the number of RFA cycles are not significantly associated with gestational age at birth.

Keywords: Fetal outcomes; Monochorionic diamniotic pregnancy; Multi-gestation; Radiofrequency ablation.