Outcomes of monochorionic twin pregnancies complicated by Type-III selective fetal growth restriction.

OBJECTIVE: Type III selective intrauterine growth restriction (sIUGR) is associated with a high and unpredictable risk of fetal death and fetal brain injury. Our objective was to describe the prospective risk of fetal death and the risk of adverse neonatal outcomes in a contemporary cohort. METHODS: We retrospectively reviewed all monochorionic diamniotic twin pregnancies complicated by type III sIUGR managed at nine fetal centers over a 12-year time period. Higher order multiples, major fetal anomalies or other monochorionicity related complications at initial presentation were excluded. Fetal and neonatal outcomes were collected and management strategies were reviewed. Composite adverse neonatal outcome was defined as neonatal death, invasive ventilation beyond the resuscitation period, culture proven sepsis, necrotizing enterocolitis (NEC) requiring treatment, intraventricular hemorrhage (IVH) >grade I, retinopathy of prematurity (ROP) >stage II or periventricular leukomalacia (PVL). The prospective risk of fetal death and the risk of neonatal complications at each gestational age were evaluated. RESULTS: We collected data on 328 pregnancies (656 fetuses). After exclusion of pregnancies which underwent selective reduction (n=18, 5.5%), there were 51 (8.3%) non-iatrogenic fetal deaths in 35 pregnancies (11.3%). Single deaths occurred in 19 (5.8%) pregnancies and double deaths in 16 (4.9%) pregnancies. The prospective risk of non-iatrogenic fetal death per fetus declined from 8.1% (95% CI 5.95-10.26) at 16 weeks, to less than 2% (95% CI 0.59-2.79) after 28.4 weeks and to less than 1% (95% CI -0.30-1.89) beyond 32.6 weeks. In otherwise uncomplicated type III sIUGR, delivery was generally planned at 32 weeks, at which time the risk of composite adverse neonatal outcomes was 29% (31/107 neonates). For twin pregnancies that continued to 34 weeks there was a very low risk of fetal demise (0.7%) and a low risk of adverse outcomes (11%). CONCLUSIONS: In this contemporary cohort from tertiary fetal centers, the risk of fetal death in type III sIUGR was lower than previously reported. Further efforts should be directed at identifying predictors of fetal death and optimal antenatal surveillance strategies to select a cohort of pregnancies that can safely continue beyond 33 weeks of gestation. This article is protected by copyright. All rights reserved.status: Published onlin