Is neonatal risk from vasa previa preventable? The 20-year experience from a single medical center

Background. Vasa previa is a rare condition associated with neonatal morbidity and mortality that may be diagnosed prenatally using transvaginal sonography. The aim of this study was to assess the prenatal detection of vasa previa and its subsequent impact on neonatal outcomes in two 10-year periods (1988-1997 versus 1998-2007). Method. Retrospective review of all cases of vasa previa. Data on obstetrical history, modes of conception, sonographic scans, delivery mode, and neonatal outcome were retrieved and recorded. Result. There were 19 pregnancies (21 neonates) with confirmed vasa previa (overall incidence of 1.7/ 10,000 deliveries). Vasa previa were diagnosed prenatally in 10 (52.6%) cases. In cases without prenatal diagnosis, there was a higher proportion of neonates with 10 Apgar score ≤5 and cord blood pH <7 compared with cases diagnosed prenatally (66.7% versus 10%, p ≤ 0.05, and 33.3% versus 0%, p < 0.05, respectively). The prenatal detection rate of vasa previa increased from 25 to 60% between the 2 time periods (p > 0.05), whereas perinatal mortality and 10 Apgar scores ≤5 decreased from 25 to 0% and from 50 to 33.3% (p > 0.05). Conclusion. Prenatal sonographic screening using targeted scans for vasa previa in women at risk or as part of routine mid-gestation scanning may significantly impact its obstetric manifestations.