Increased incidence of respiratory distress syndrome in neonates of mothers with abnormally invasive placentation.

backgroundThe incidence of abnormally invasive placentation (AIP) is increasing. Most of these pregnancies are delivered preterm. We sought to characterize neonatal outcomes in AIP pregnancies.

methodsIn this retrospective case-control study (2006-2015), AIP neonates (n = 108) were matched to two controls each for gestational age, antenatal glucocorticoid exposure, sex, plurity, and delivery mode. Medical records were reviewed for neonatal and maternal characteristics/outcomes. Univariate and multivariate Poisson regressions were performed to determine relative risk ratios (RR).

resultsThere were no mortalities. All neonatal outcomes were similar except for respiratory distress syndrome (RDS), which affected 37% of AIP neonates (versus 21% of controls). AIP neonates required respiratory support (64.8% vs. 51.9%) and continuous positive airway pressure (53.7% vs. 42.1%) for a longer duration. Univariate regression yielded elevated RRs for RDS for AIP (RR 1.78, 95% CI 1.24-2.54), placenta previa (RR = 1.94, 95% CI 1.36-2.76), and placenta previa with bleeding (RR 2.29, 95% CI 1.36-3.86). One episode of bleeding had a RR of 2.43 (95% CI 1.57-3.76), 2 or more episodes had a RR of 2.95 (95% CI 1.96-4.44), and bleeding/abruption as the delivery indication had a RR of 2.57 (95% CI 1.82-3.64). A multivariate regression stratifying for AIP and evaluating the combined and individual associations of AIP, bleeding, placenta previa, and GA, resulted in elevated RRs for placenta previa alone (RR 2.16, 95% CI 1.15-4.06) and placenta previa and bleeding (RR 1.69, 95% CI 1.001-2.85).

conclusionsThe increased incidence of RDS at later gestational ages in AIP is driven by placenta previa. AIP neonates required respiratory support for a longer duration than age-matched controls. Providers should be prepared to counsel expectant parents and care for affected neonates.