Clinical Outcomes of Twin Reversed Arterial Perfusion ( <scp>TRAP</scp> ) Sequence: A Retrospective Analysis From a Tertiary Center

Twin Reversed Arterial Perfusion (TRAP) sequence is a rare complication of monochorionic twin pregnancies characterized by reversed blood flow from the pump twin to a nonviable acardiac twin. This study aims to share the clinical outcomes and procedural details of TRAP sequence cases managed at our tertiary fetal therapy center, with emphasis on various intrauterine treatment modalities. We conducted a retrospective review of 20 pregnancies diagnosed with TRAP sequence and managed at a tertiary fetal therapy unit between January 2018 and July 2025. Diagnosis was confirmed via prenatal ultrasonography and Doppler imaging. Patients underwent intrauterine intervention-radiofrequency ablation (RFA), microwave ablation (MWA), intrafetal laser (IFL), or bipolar cord coagulation-based on gestational age, acardiac twin size, and hemodynamic status of the pump twin. Twenty pregnancies diagnosed with TRAP sequence were included. The median maternal age was 32 years (range: 22-47). Both diagnosis and intervention occurred at a median gestational age of 20 weeks (range: 12-29). Invasive treatment was performed in 19 cases: RFA (n = 10), IFL (n = 4), cord coagulation (n = 3), and MWA (n = 2). The median time from procedure to delivery was 98 days (range: 1-135). Overall live birth rate was 80% (16/20), and neonatal survival rate was 75% (15/20). Fetal interventions can significantly enhance survival in TRAP pregnancies, including those referred at advanced gestational ages. Early identification of risk indicators and tailored procedural planning are critical for improving outcomes. Our findings underscore the efficacy of minimally invasive therapies in optimizing prognosis for the pump twin.