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OBJECTIVE: There are conflicting data on whether fetoscopic laser photocoagulation of placental anastomoses (FLP) for treating twin-to-twin transfusion syndrome (TTTS) is associated with lower rates of overall survival. The objective of this study is to characterize survival and other associated morbidity after FLP across gestational ages of FLP. METHODS: This is a secondary analysis of prospectively collected data on patients with monochorionic-diamniotic twins that had FLP for TTTS at two centers between 2011 and 2022. Patients were divided into gestational age epochs for FLP before 18 wks, 18 0/7 - 19 6/7 wks, 20 0/7 - 21 6/7 wks, 22 0/7 - 23 6/7 wks, 24 0/7 - 25 6/7 wks and after 26 wks. Demographic characteristics, sonographic characteristics of TTTS and operative characteristics were compared across the gestational age epochs. Outcomes including overall survival, preterm delivery, preterm prelabor rupture of membranes (PPROM), intrauterine fetal demise (IUFD) and neonatal demise (NND) were also compared across gestational age epochs. Multivariate analysis was performed by fitting logistic regression models for these outcomes. Kaplan-Mejer curves were constructed to compare the interval from PPROM to delivery for each gestational age epoch. RESULTS: There were 768 patients that met inclusion criteria. The dual survival rate was 61.3% for FLP performed prior to 18 weeks compared to 78.0% - 86.7% across later gestational age epochs. This appears to be related to increased rates of donor IUFD following FLP performed before, versus after 18 weeks (28.0% vs. 9.3% - 14.1%). Rates of recipient IUFD/NND and donor NND were similar regardless of gestational age of FLP. Rates of PPROM were higher for earlier FLP, ranging from 45.6% for FLP before 18 weeks to 11.9% for FLP at 24 - 26 weeks gestational age. However, the gestational age of delivery was similar across gestational age epochs with a median of 31.7 weeks. In multivariate analysis, donor loss was independently associated with FLP before 18 weeks after adjusting for selective fetal growth restriction, Quintero stage and other covariates. PPROM and PTD were also associated with FLP before 18 weeks after adjusting for cervical length, placental location, trocar size, laser energy and amnioinfusion. CONCLUSION: FLP performed at earlier gestational ages is associated with lower overall survival, which is driven by higher risk of donor IUFD, as opposed to differences in PPROM or PTD. Counseling regarding survival should account for gestational age of presentation. This article is protected by copyright. All rights reserved.
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OBJECTIVES: The congenital lung malformation volume ratio (CVR) is a prenatal ultrasound measurement that parameterizes congenital lung malformation (CLM) size. The aims of this study were to use serial measurements to create estimated growth curves of fetal CVR for asymptomatic and symptomatic neonates with CLM and to investigate whether a discriminant prognostic model based on these measurements could predict accurately which fetuses with CLM will require invasive respiratory support at delivery and should therefore be delivered at a tertiary-care facility. METHODS: This was a retrospective study of fetuses diagnosed prenatally with CLM at three tertiary-care children's hospitals between 2009 and 2016. Those with two or more sonographic measurements of CVR were included. Serial fetal CVR measurements were used to create estimated growth curves for neonates with and those without respiratory symptoms at delivery, defined as requiring invasive respiratory support for the first 24 h after delivery. A discriminant model based on serial CVR measurements was used to calculate the dynamic probability of the need for invasive respiratory support. The performance of this model overall and in preterm and term neonates was compared with those using maximum CVR thresholds of 1.0 and 1.6. RESULTS: Of the 147 neonates meeting the inclusion criteria, 16 (10.9%) required postnatal invasive respiratory support. The estimated CVR growth curve models showed different growth trajectories for asymptomatic and symptomatic neonates, with significantly higher CVR in symptomatic neonates, and values peaking late in the second trimester at around 25 weeks' gestation in asymptomatic neonates. All prognostic methods had high accuracy for the prediction of the need for invasive respiratory support in term neonates, but the discriminant model had the best performance overall (area under the receiver-operating characteristics curve (AUC) = 0.88) and in the preterm population (AUC = 0.85). CONCLUSIONS: The estimated CVR growth curves showed different growth patterns in asymptomatic and symptomatic neonates with CLM. The dynamic discriminant model performed well overall and particularly in neonates that were carried to term. Development of an externally validated clinical tool based on this analysis could be useful in determining the site of delivery for fetuses with CLM. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.