1018 Microscopic focus of accreta on placental pathology: clinical context impacts morbidity risks in subsequent pregnancy

Abstract

To describe association of microscopic focus of placenta accreta (MFPA) with subsequent pregnancy outcomes, and to compare outcomes among women with incidentally identified MFPA and those with symptomatic MFPA. Retrospective cohort of all deliveries at Kaiser Permanente Northern California from 2008-2019. A search of placental pathology database identified all cases with an index finding of MFPA and subsequent delivery of a live singleton. Index pregnancies with MFPA were categorized as asymptomatic (aMFPA) or symptomatic (sMFPA) by absence or presence of hemorrhagic morbidity and/or clinically adherent placenta. Rates of hemorrhagic morbidity and clinically adherent placenta in the subsequent pregnancy were compared among aMFPA and sMFPA index pregnancies in bivariate analysis and multivariate models controlling for potential confounders. Of 140 patients with MFPA in the index pregnancy, 64% were asymptomatic and 36% were symptomatic. Of the entire cohort, 28% had hemorrhagic morbidity and/or adherent placenta in the subsequent pregnancy. sMFPA in the index pregnancy was associated with higher rate of subsequent hemorrhagic morbidity and/or adherent placenta compared to aMFPA (39% vs 8%, p < 0.0001; Table 1). After adjusting for age, race, parity, body mass index, in-vitro fertilization, prior uterine surgery, cesarean delivery, and placenta previa, sMFPA in the index pregnancy was highly associated with hemorrhagic morbidity and/or adherent placenta compared to aMFPA (aOR 11.5, 95% CI 2.9-45.8). Of 71 patients with placental pathology in the subsequent pregnancy, 32% had recurrent MFPA. Recurrent MFPA was associated with increased morbidity compared to those without recurrence or those with no placental pathology (61% vs 40% vs 9%, p<0.0001; Table 2). Symptomatic MFPA is highly associated with hemorrhagic morbidity and/or adherent placenta in the next pregnancy compared with incidentally identified MFPA, particularly if MFPA is recurrent. This data can inform counseling and management of women with MFPA planning subsequent pregnancies.View Large Image Figure ViewerDownload Hi-res image Download (PPT)