Placental and uterine pathology in women undergoing peripartum hysterectomy

Objective: To estimate if peripartum hysterectomies performed for intractable uterine atony have pathologic findings consistent with infection more often than those hysterectomies performed for other indications. Methods: This is a retrospective cohort study of all consecutive peripartum hysterectomies at our institution from 1988 to 2009. Scheduled cesarean hysterectomies were excluded. Maternal, fetal, and pathologic data were obtained by medical record review. Pathologic evaluation was performed for each specimen per a standardized protocol. Patients undergoing hysterectomy for uterine atony were compared with those requiring hysterectomy for another indication. Pearson's χ ² and Student's t test were used for analysis. Results: Of 324,654 deliveries during the study period, 558 (1.7%) women underwent emergent peripartum hysterectomies; 190 (34%) were for intractable uterine atony. Those requiring hysterectomy for uterine atony were more likely to be at term (87% compared with 62%), have clinical chorioamnionitis (19% compared with 6%), and have longer labors (8 hours compared with 2.5 hours). Certain placental pathologic findings were significantly more common in the atony group, including chorioamnionitis, umbilical vasculitis, chorionic plate vasculitis, and funisitis. Acute endometritis and cervicitis were also more common in the atony group. Conversely, abnormal placental implantation (37% compared with 8%) and leiomyomas (21% compared with 8%) were significantly more common in the group requiring hysterectomy for other indications. Conclusion: Patients requiring emergent peripartum hysterectomies as a result of intractable uterine atony are more likely to have clinical and pathologic findings consistent with acute inflammation and infection.