528: North American Fetal Therapy Network: Indications for delivery following laser ablation for twin-twin transfusion syndrome

Abstract

Despite improvements in fetal survival for pregnancies affected by twin-twin transfusion syndrome (TTTS) since the introduction of laser photocoagulation, prematurity remains a major source of morbidity and mortality. To investigate the role that iatrogenic and procedure-related factors contribute to prematurity, we collected information regarding timing and indication for delivery following laser treatment in a multicenter cohort. Eleven centers from the North American Fetal Therapy Network (NAFTNet) conducted a retrospective review of consecutive cases of TTTS undergoing laser treatment recording clinical and ultrasound variables including TTTS Stage and gestational age (GA) at treatment and delivery. The route as well as the primary and secondary maternal or fetal indications for delivery were noted. Spearman correlations were utilized to determine variables with significant correlation with latency and GA at delivery. Multivariable modeling was utilized to determine the strongest associations. A total of 749 pregnancies were analyzed. Treatment details and outcomes are listed in Table 1. After laser, average latency is 10.2 ± 4.8 weeks and mean GA at delivery 30.7 ± 4.5 weeks. Primary maternal indications for delivery comprised 75% of cases and included spontaneous labor (46.2%), premature rupture of membranes (PROM) (17.6%), and abruption (8.1%). Primary fetal indications included donor non-reassuring fetal surveillance (20.8%), donor growth restriction (16.1%) and abnormal Doppler (16.1%). The most common secondary indications for delivery are PROM, spontaneous labor and donor growth restriction. Table 2 lists the variables with significant correlations to GA at delivery or latency under univariate analysis. After multivariable modeling, cerclage and fetoscopic complications are associated with shorter latency and earlier GA at delivery whereas a history of preterm birth is associated with shorter latency. In our cohort, premature delivery after laser therapy was primarily due to spontaneous labor, PROM or concern regarding the donor. Both modifiable and non-modifiable factors correlated with earlier delivery and shorter latency. Future research should be directed toward the goal of prolonging pregnancy to further reduce morbidity and mortality associated with TTTS.View Large Image Figure ViewerDownload Hi-res image Download (PPT)