OP15.06: Monochorionic twins complicated by twin anemia polycythemia sequence: perinatal outcome following intrauterine blood transfusion

To determine the perinatal outcome of monochorionic twin pregnancies complicated by twin anemia polycythemia sequence (TAPS) and treated by intrauterine blood transfusion. All monochorionic twins diagnosed with TAPS between 2012 and 2016 at a single fetal therapy centre and that underwent intrauterine transfusion (IUT) were included. Neonatal mortality and morbidity were evaluated. Severe central nervous system (CNS) injury was defined as IVH grade 3-4, ischemic foci or periventricular leukomalacia. During the study period, 225 monochorionic twins were followed at our centre, of whom 70 underwent laser ablation due to Twin–twin transfusion syndrome. TAPS was diagnosed in 15 cases; 10 of them were spontaneous and 5 occurred following laser surgery. Out of 12 patients diagnosed prenatally with TAPS, 7 cases were treated with intrauterine blood transfusion for the anemic twin. The median gestational age at diagnosis was 25.3 weeks of gestation (range 24-27) and the first IUT was performed at 27.4 weeks of gestation (range 25.1-29.3). Four patients required a second IUT 4-21 days after the first one. The median gestational age at delivery was 30 weeks of gestation (range 26.7-32.6) with an interval of 17 days (range 3-44) between the first IUT and delivery resulting in survival of 13 (93%) of the neonates. All of the polycythemic twins survived, two of them were complicated by severe CNS injury. Among the anemic twins, there was one neonatal death following delivery at 26.7 weeks of gestation, but none of the six anemic survivors suffered from severe brain injury. Monochorionic twin pregnancies complicated by TAPS diagnosed at late second trimester can be managed by IUT of the anemic twin allowing deferral of delivery and resulting in favourable neonatal outcome. 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.