OP11.09: The outcomes and prognostic factors of stage 1 twin–twin transfusion syndrome following fetoscopic laser photocoagulation

There remains controversy about the significance of fetoscopic laser photocoagulation (FLP) for stage 1 twin–twin transfusion syndrome (TTTS). The aim of this study was to clarify outcomes and prognostic factors of stage 1 TTTS following laser surgery in Japan. We conducted a retrospective cohort study of cases with stage 1 TTTS who underwent fetoscopic laser surgery at six centres in Japan from 2002 to 2021. The primary outcome was neonatal survival at 28 days of age. We used univariate logistic regression analysis to assess the association between preoperative or intraoperative factors and neonatal survival for recipient and donor, respectively. Multiple logistic regression analysis was performed for using factors that had a P value < 0.2 in univariate analysis. A total of 272 cases were included in the study. Recipient survival was in 253 cases (93%), included four of miscarriage, 12 of fetal demise, and three of neonatal death. No factor was associated with recipient survival. Among donors, 246 cases (90%) survived at 28 days. The details of the cases with poor outcome were four of miscarriage, 19 of fetal demise, and three of neonatal death. Preoperative twin anemia polycythemia sequence (TAPS) (aOR, 17.45; 95% CI, 3.16-96.31) and arterioarterial vascular anastomosis (AAA) identified at FLP (aOR, 2.78; 95% CI, 1.10-7.06) were significantly associated with poor outcomes for donors. Survival rate of stage 1 TTTS after FLP was over 90% for both recipients and donors. Preoperative TAPS and AAA were independent risk factors for poor outcome in donors. Unstable hemodynamics caused by AAA might affect donor same as cases of stage 3 atypical.