Complicated placenta accreta spectrum: identifying a high-risk cohort

To assess differences in the perioperative complication rate between patients with placenta accreta spectrum (PAS) with and without complicating factors.

This retrospective cohort study included subjects who underwent cesarean hysterectomy with histology-proven PAS between 23 0/7 and 42 0/7 weeks gestational age (GA) from 1 July 2008 to 11 April 2017. Perioperative outcomes were compared between those with uncomplicated PAS and "complicated PAS," defined as PAS subjects who experienced ≥2 bleeding episodes, preterm premature rupture of membranes (PPROM), or premature contractions requiring tocolysis.

Overall, 26 complicated PAS and 27 uncomplicated PAS cases were compared; no difference in the rate of perioperative complications was identified. An increased proportion of complicated PAS cases required blood product transfusion before delivery: 2 (40%), 3 (27.3%), and 2 patients (20%) for those with PPROM, preterm contractions, and ≥2 bleeding episodes respectively, compared to patients with uncomplicated PAS, having no transfusions (p = .001). Time of delivery was earlier for patients with complicated compared to uncomplicated PAS (median GA 30.9 [Q1 = 27.9; Q3 = 31.9] and 34.9 [Q1 = 32.1; Q3 = 35.7], p < .001). Median birthweights were lower (p < .0144) and maternal length of stay longer (p < .0012) for complicated PAS.

Patients with complicated PAS were not at higher risk for perioperative complications but were associated with earlier delivery, required more antenatal blood transfusions, and had a longer LOS.