Pre- and Periviable PPROM after Fetoscopic Laser Surgery: Are Survival Outcomes Better than We Think?

Introduction: Limited data exist regarding outcomes when pre- and periviable PPROM (PPROM ≤26 weeks of gestation) occurs as a complication of fetoscopic laser surgery (FLS) for twin-twin transfusion syndrome (TTTS).

Methods: This is a retrospective cohort study of FLS cases performed at a single institution between January 2015 and May 2021. Study inclusion was limited to patients with monochorionic-diamniotic twin pregnancies complicated by TTTS who underwent FLS. Patients were grouped by pPPROM status, and further stratified to those continuing with expectant management, and outcomes were compared between groups. The primary outcome was survival to live birth of at least one twin.

Results: During the study period, 171 patients underwent FLS and a total of 96 (56.1%) subjects satisfied inclusion criteria. Among included subjects, 18 (18.8%) experienced pPPROM after FLS and 78 (81.2%) did not. Baseline characteristics were similar between groups. Among patients with pPPROM, 11 (61.1%) pursued expectant management and 7 (38.9%) opted for pregnancy termination. Among expectantly managed subjects, median pPPROM-to-delivery interval was 47.0 days (6.0-66.0 IQR) with a median gestational age at delivery of 29+1 weeks (24 + 4-33 + 6 IQR). Rates of survival to live birth of at least one twin (90.9% vs. 96.2% p = 0.42) were similar between those with pPPROM undergoing expectant management and those without pPPROM. Dual survivorship (45.5% vs. 78.2%, p = 0.03), perinatal survival to live birth (68.2% vs. 87.2%, p = 0.05), and perinatal survival to newborn hospital discharge (59.1% vs. 85.9%, p = <0.01) were all significantly lower among those with pPPROM. Gestational age at delivery was lower among those continuing with pregnancies complicated by pPPROM (29 + 1 vs. 32+5 weeks, p = <0.01).

Conclusion: Survival of at least one twin to live birth remained high among those pursing expectant management after experiencing post-FLS pPPROM, suggesting that the outlook after this complication is not necessarily poor. However, this complication was associated with lower chances of dual survival and greater prematurity.