Risk factors for placenta accreta spectrum disorders in women with any prior cesarean and a placenta previa or low lying: a prospective population-based study.

This study aimed to identify the risk factors for placenta accreta spectrum (PAS) in women who had at least one previous cesarean delivery and a placenta previa or low-lying. The PACCRETA prospective population-based study took place in 12 regional perinatal networks from 2013 through 2015. All women with one or more prior cesareans and a placenta previa or low lying were included. Placenta accreta spectrum (PAS) was diagnosed at delivery according to standardized clinical and histological criteria. Of the 520,114 deliveries, 396 fulfilled inclusion criteria; 108 were classified with PAS at delivery. Combining the number of prior cesareans and the placental location yielded a rate ranging from 5% for one prior cesarean combined with a posterior low-lying placenta to 63% for three or more prior cesareans combined with placenta previa. The factors independently associated with PAS disorders were BMI ≥ 30, previous uterine surgery, previous postpartum hemorrhage, a higher number of prior cesareans, and a placenta previa. Finally, in this high-risk population, the rate of PAS disorders varies greatly, not only with the number of prior cesareans but also with the exact placental location and some of the women's individual characteristics. Risk stratification is thus possible in this population.

Conservative management or cesarean hysterectomy for placenta accreta spectrum: the PACCRETA prospective study.

BACKGROUND: Placenta accreta spectrum is a life-threatening condition that has increased dramatically in recent decades along with cesarean rates worldwide. Cesarean hysterectomy is widely practiced in women with placenta accreta spectrum; however, the maternal outcomes after cesarean hysterectomy have not been thoroughly compared with the maternal outcomes after alternative approaches, such as conservative management. OBJECTIVE: This study aimed to compare the severe maternal outcomes between women with placenta accreta spectrum treated with cesarean hysterectomy and those treated with conservative management (leaving the placenta in situ). STUDY DESIGN: From a source population of 520,114 deliveries in 176 hospitals (PACCRETA study), we designed an observational cohort of women with placenta accreta spectrum who had either a cesarean hysterectomy or a conservative management (the placenta left in situ) during cesarean delivery. Clinicians prospectively identified women meeting the inclusion criteria and included them at delivery. Data collection started only after the women had received information and agreed to participate in the study in the immediate postpartum period. The primary outcome was the transfusion of >4 units of packed red blood cells within 6 months after delivery. Secondary outcomes were other maternal complications within 6 months. We used propensity score weighting to account for potential indication bias. RESULTS: Here, 86 women had conservative management and 62 women had cesarean hysterectomy for placenta accreta spectrum during cesarean delivery. The primary outcome occurred in 14 of 86 women in the conservative management group (16.3%) and 36 of 61 (59.0%) in the cesarean hysterectomy group (risk ratio in propensity score weighted model, 0.29; 95% confidence interval, 0.19-0.45). The rates of hysterectomy, total estimated blood loss exceeding 3000 mL, any blood product transfusion, adjacent organ injury, and nonpostpartum hemorrhage-related severe maternal morbidity were lower with conservative management than with cesarean hysterectomy (all adjusted, P≤.02); but, the rates of arterial embolization, endometritis, and readmission within 6 months of discharge were higher with conservative management than with cesarean hysterectomy. CONCLUSION: Among women with placenta accreta spectrum who underwent cesarean delivery, conservative management was associated with a lower risk of transfusion of >4 units of packed red blood cells within 6 months than cesarean hysterectomy.