Objectives Twin anemia- polycythemia sequence (TAPS) is associated with increased perinatal morbidity and mortality. Inconsistencies in the diagnostic criteria for TAPS exist, which hinder the... Show moreObjectives Twin anemia- polycythemia sequence (TAPS) is associated with increased perinatal morbidity and mortality. Inconsistencies in the diagnostic criteria for TAPS exist, which hinder the ability to establish robust evidence-basedmanagement or monitoring protocols. The main aim of this study was to determine, by expert consensus using a Delphi procedure, the key diagnostic features and optimal monitoring approach for TAPS.Methods A Delphi process was conducted among an international panel of experts on TAPS. Panel members were provided with a list of literature-based parameters for diagnosing and monitoring TAPS. They were asked to rate the importance of the parameters on a five-point Likert scale. Consensus was sought to determine the cut-off values for accepted parameters, as well as parameters used in the monitoring of and assessment of outcome in twin pregnancy complicated by TAPS.Results A total of 132 experts were approached. Fifty experts joined the first round, of whom 33 (66%) completed all three rounds. There was agreement that the monitoring interval for the development of TAPS should be every 2 weeks and that the severity should be assessed antenatally using a classification system based on middle cerebral artery (MCA) peak systolic velocity (PSV), but there was no agreement on the gestational age at which to start monitoring. Once the diagnosis of TAPS is made, monitoring should be scheduled weekly. For the antenatal diagnosis of TAPS, the combination of MCA-PSV >= 1.5 MoM in the anemic twin and <= 0.8 MoM in the polycythemic twin was agreed. Alternatively, MCA-PSV discordance >= 1 MoM can be used to diagnose TAPS. Postnatally, hemoglobin difference >= 8g/dL and intertwin reticulocyte ratio >= 1.7 were agreed criteria for diagnosis of TAPS. There was no agreement on the cut-off of MCA-PSV or its discordance for prenatal intervention. The panel agreed on prioritizing perinatal and long-term survival outcomes in follow-up studies.Conclusions Consensus-based diagnostic features of TAPS, as well as cut-off values for the parameters involved, were agreed upon by a panel of experts. Future studies are needed to validate these diagnostic features before they can be used in clinical trials of interventions. Copyright (C) 2019 ISUOG. Published by John Wiley & Sons Ltd. Show less
Objective To investigate the antenatal management and outcome in a large international cohort of monochorionic twin pregnancies with spontaneous or post-laser twin anemia-polycythemia sequence ... Show moreObjective To investigate the antenatal management and outcome in a large international cohort of monochorionic twin pregnancies with spontaneous or post-laser twin anemia-polycythemia sequence (TAPS).Methods This study analyzed data of monochorionic twin pregnancies diagnosed antenatally with spontaneous or post-laser TAPS in 17 fetal therapy centers, recorded in the TAPS Registry between 2014 and 2019. Antenatal diagnosis of TAPS was based on fetal middle cerebral artery peak systolic velocity > 1.5 multiples of the median (MoM) in the TAPS donor and < 1.0 MoM in the TAPS recipient. The following antenatal management groups were defined: expectant management, delivery within 7 days after diagnosis, intrauterine transfusion (IUT) (with or without partial exchange transfusion (PET)), laser surgery and selective feticide. Cases were assigned to the management groups based on the first treatment that was received after diagnosis of TAPS. The primary outcomes were perinatal mortality and severe neonatal morbidity. The secondary outcome was diagnosis-to-birth interval.Results In total, 370 monochorionic twin pregnancies were diagnosed antenatally with TAPS during the study period and included in the study. Of these, 31% (n=113) were managed expectantly, 30% (n=110) with laser surgery, 19% (n=70) with IUT (+/- PET), 12% (n=43) with delivery, 8% (n=30) with selective feticide and 1% (n=4) underwent termination of pregnancy. Perinatal mortality occurred in 17% (39/225) of pregnancies in the expectant-management group, 18% (38/215) in the laser group, 18% (25/140) in the IUT (+/- PET) group, 10% (9/86) in the delivery group and in 7% (2/30) of the cotwins in the selective-feticide group. The incidence of severe neonatal morbidity was 49% (41/84) in the delivery group, 46% (56/122) in the IUT (+/- PET) group, 31% (60/193) in the expectant-management group, 31% (57/182) in the laser-surgery group and 25% (7/28) in the selective-feticide group. Median diagnosis-to-birth interval was longest after selective feticide (10.5 (interquartile range (IQR), 4.2-14.9) weeks), followed by laser surgery (9.7 (IQR, 6.6-12.7) weeks), expectant management (7.8 (IQR, 3.8-14.4) weeks), IUT (+/- PET) (4.0 (IQR, 2.0-6.9) weeks) and delivery (0.3 (IQR, 0.0-0.5) weeks). Treatment choice for TAPS varied greatly within and between the 17 fetal therapy centers.Conclusions Antenatal treatment for TAPS differs considerably amongst fetal therapy centers. Perinatal mortality and morbidity were high in all management groups. Prolongation of pregnancy was best achieved by expectant management, treatment by laser surgery or selective feticide. (C) 2020 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of the International Society of Ultrasound in Obstetrics and Gynecology. Show less