Predictive Indicators and Outcomes of Pregnancies Affected by Stage I Twin-Twin Transfusion Syndrome Treated With Fetoscopic Laser Photocoagulation.

Objective: The significance of fetoscopic laser photocoagulation (FLP) in stage I twin-twin transfusion syndrome (TTTS) remains controversial. This study aimed to clarify the outcomes and prognostic factors of stage I TTTS after FLP.

Method: We conducted a retrospective cohort study on patients with stage I TTTS who underwent FLP in Japan. The primary outcome was neonatal survival at 28 days. The adjusted odds ratios (aOR) of pre- and intraoperative factors for mortality in recipient and donor twins were calculated.

Results: This study included 272 twin pairs. The survival rate of at least one twin and both twins was 98% (267 pairs) and 85% (232 pairs), respectively. Survival of the recipient twin was observed in 253 cases (93%). No factor was associated with the mortality of the recipients. Among the donor twins, 246 (90%) survived. Preoperative twin anemia-polycythemia sequence (aOR, 17.45; 95% CI, 3.16-96.31) and arterio-arterial vascular anastomosis (AAA) identified at FLP (aOR, 2.78; 95% CI, 1.10-7.06) were independently associated with mortality of the donors.

Conclusion: The neonatal survival rate for both recipient and donor twins was > 90% among patients with stage I TTTS who underwent FLP. AAA is a risk factor for mortality in donors following FLP, though the pathophysiology of AAA remains to be clarified.