VP22.03: Fetoscopic laser for Twin–twin transfusion syndrome using low power

Twin–twin transfusion syndrome (TTTS) complicates 9–15% of monochorionic twin pregnancies and is a major cause of morbidity and death. Contemporary therapy of choice has become fetoscopic laser ablation of the placenta. The procedure varies by institution, with instrument and laser choice based on availability and operator preference. We present our 4-year-experience with fetoscopic laser for TTTS, in a single, tertiary institution using very low laser power and compare our results with published data. Descriptive case series of all fetoscopic laser procedures performed for TTTS at Yale New Haven Hospital from August 2016 to May 2020 with known pregnancy outcomes. Procedures were performed by a single surgeon, utilising a diode laser (power 3 watts, wavelength 532nm). Gestational age (GA) at procedure and delivery are reported as mean ( ± standard deviation). Survival to delivery >24 weeks is reported as percent. A total of 40 fetoscopic laser procedures were performed for TTTS, with known outcomes in 20. Mean GA at procedure was 20.0 ± 2.3 weeks. 18 pregnancies resulted in at least 1 survivor to delivery (90%); 5 had 1 survivor (25%) and 13 had 2 survivors (65%). 2 pregnancies had dual fetal demise or delivered <24 weeks (10%). Preterm premature rupture of membranes (PPROM) occurred in 6 pregnancies (30%). Mean GA at delivery was 32.3 ± 4.7 weeks. Rate of fetal survival after fetoscopic laser for TTTS using low power are similar to previously reported outcomes, with possible lower PPROM risks. Supporting information can be found in the online version of this abstract Supporting Information Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.