Fatal fetal abnormality Irish live-born survival-an observational study

J Community Genet. 2021 Oct;12(4):643-651. doi: 10.1007/s12687-021-00534-3. Epub 2021 Jul 2.

Abstract

The aim of the study was to provide accurate information regarding live-born infant survival after diagnosis of fatal fetal anomaly (FFA) to aid decision-making in respect of pregnancy management, and to ascertain the natural history of live-born infants with FFAs via a retrospective analysis of death records (2006-2018), from the National Paediatric Mortality Registry (source Central Statistics Office 2019). Diagnoses and survival times were ascertained from narrative records with further ascertainment and reconciliation of trisomies 13 and 18 cases by review of cytogenetic test records, the National Death Events Register and National Perinatal Epidemiology Centre data. During the study period, termination of pregnancy was not permitted under the Irish Constitution. Patients are live-born babies with fatal fetal anomalies whose deaths were registered in the Republic of Ireland. The main outcome measure was construction of anomaly-specific survival curves, or survival time range and median for those anomalies with rare occurrence. Survival curves for anencephaly, bilateral renal agenesis, thanatophoric dysplasia, trisomy 13, and trisomy 18 show that 90% (n = 95), 93% (n = 60), 100% (n = 14), 37% (n = 92) and 33% (n = 162), respectively, were deceased by 24 h and 98%, 100%, 100%, 73%, and 53%, respectively, by 1 week post-delivery. Survival time range and median were calculated for triploidy (3.5 h-20 days; 10.5 days), whose occurrence was rare. Anhydramnios, craniorachischisis, hydranencephaly and severe hydrocephalus were extremely rare and all deaths were neonatal deaths. Our results provide 13 years of national natural history data of live birth FFA survival. This provides objective information to aid obstetric counselling of couples upon diagnosis of an FFA.

Keywords: Anencephaly; Fatal fetal abnormality; Live-born survival; Renal agenesis; Thanatophoric dysplasia; Trisomy 13; Trisomy 18.