Vasa previa: a multicenter retrospective cohort study

Objective: The objective of the study was to describe the characteristics and outcomes of patients with antenatal diagnosis of vasa previa and evaluate the predictive factors of resolution in a contemporary large, multicenter data set. Study Design: This was a retrospective multicenter cohort study of all antenatally diagnosed cases of vasa previa, identified via ultrasound and electronic medical record, between January 2011 and July 2018 in 5 US centers. Records were abstracted to obtain variables at diagnosis, throughout pregnancy, and outcomes, including maternal and neonatal variables. Data were reported as median [range] or n (percentage). Descriptive statistics, receiver-operating characteristics, and logistic regression analysis were used as appropriate. Results: One hundred thirty-six cases of vasa previa were identified in 5 centers during the study period, 19 (14%) of which resolved spontaneously at median estimated gestational age of 27 weeks [19–34]. All subjects with unresolved vasa previa underwent cesarean delivery at a median estimated gestational age of 34 weeks [27–39] with the median estimated blood loss of 800 mL [250–2000]. Rates for vaginal bleeding, preterm labor, premature rupture of membrane, and need for blood product transfusion were not different between the resolved and unresolved group (P = NS). The odds ratio for resolution in those with the estimated gestational age of less than 24 weeks at the time of diagnosis was 7.9 (95% confidence interval, 2.1–29.4) after adjustment for confounding variables. Conclusion: Our data suggest that outcomes in antenatally diagnosed cases of vasa previa are excellent. Furthermore, our data report a higher chance of resolution when the condition is diagnosed before 24 weeks of gestation.