Trends, characteristics, and outcomes of placenta accreta spectrum: A national study in the United States

ABSTRACT Background Although an infrequent occurrence, the placenta can adhere abnormally to the gravid uterus leading to significantly high maternal morbidity and mortality during cesarean section (CS). Contemporary national statistics related to a morbidly adherent placenta, referred to as placenta accreta spectrum (PAS), are needed. Objective To examine national trends, characteristics, and perioperative outcomes of women who underwent CS for PAS in the United States. Methods This is a population-based retrospective, observational study querying the National Inpatient Sample. The study cohort included women who underwent CS from 10/2015-12/2017 and had a diagnosis of PAS. The main outcome measures were patient characteristics and surgical outcomes related to PAS assessed by the generalized estimating equation on multivariable analysis. Temporal trend of PAS was also assessed by linear segmented regression with log transformation. Results Of 2,727,477 cases that underwent CS during the study period, 8,030 (0.29%) had the diagnosis of PAS. Placenta accreta was the most common diagnosis (n=6,205, 0.23%), followed by percreta (n=1,060, 0.04%) and increta (n=765, 0.03%). The number of PAS cases increased by 2.1% every quarter-year from 0.27% to 0.32% (P=0.004). On multivariable analysis, (i) patient demographics: older age, tobacco use, recent diagnosis, higher comorbidity, and use of assisted reproductive technology, (ii) pregnancy characteristics: placenta previa, prior CS, breech presentation, and grand multiparity, and (iii) hospital factors: urban-teaching center and large bed capacity hospital, represented the independent characteristics related to PAS (all, P Conclusion Patient characteristics and outcomes differ across the PAS subtypes and women with placenta increta and percreta have considerably high surgical morbidity and mortality risks. One in 313 women undergoing CS had a diagnosis of PAS by the end of 2017 and the incidence appears to be higher than reported in previous studies.