Severe maternal morbidity contributed by obstetric hemorrhage: Maryland, 2020-2022.

Background: Obstetric hemorrhage is the leading cause of maternal mortality and severe maternal morbidity (SMM) in Maryland and nationally. Currently, through a quality collaborative, the state is implementing the Alliance for Innovation on Maternal Health (AIM) patient safety bundle on obstetric hemorrhage.

Objective: To describe SMM events contributed by obstetric hemorrhage and their preventability in Maryland.

Study Design: This cross-sectional study used data from hospital-based SMM surveillance and review program in Maryland. Hospital-based SMM criteria include admission to an intensive care unit and/or transfusion of 4 or more units of blood products (of any type) during pregnancy or within 42 days postpartum. A total of 193 obstetric hemorrhage events that met the surveillance definition were identified in hospitals participating in SMM surveillance since inception on August 1, 2020 until December 31, 2022. We compared patient and delivery characteristics, practices done well, and recommendations for care improvement among patients with severe obstetric hemorrhage deemed preventable and non-preventable by hospital-based review committees. For obstetric hemorrhage events deemed preventable, we further identified factors that contributed to the SMM outcome at the provider, system, and patient levels.

Results: Uterine atony was the leading cause of obstetric hemorrhage events (37.8%), followed by uterine rupture, laceration and intra-abdominal bleeding (23.8%). Sixty-six (34.2%) obstetric hemorrhage events were preventable. Patients with preventable obstetric hemorrhage were significantly more likely to have an emergency than planned cesarean delivery and less likely to have a placental complication or >1,500mL blood loss volume. Hospital-based review committees determined that 81.8%, 30.3%, and 22.7% of preventable events could have been prevented or made less severe through changes to provider, system, or patient factors, respectively. Recommendations following event reviews aligned with the Alliance for Innovation on Maternal Health Obstetric Hemorrhage Patient Safety Bundle, particularly regarding elements in the Recognition and Prevention and Response domains.

Conclusion: About one-third of SMM events contributed by obstetric hemorrhages were deemed preventable. Of AIM bundle elements, assessing hemorrhage risk on admission to labor and delivery, peripartum, and upon transition to postpartum care together with rapid, unit-standardized management of hemorrhage are likely to benefit more than half of patients with preventable SMM contributed by obstetric hemorrhage.