title: Second-line uterotonics and the risk of hemorrhage-related morbidity.
abstract: OBJECTIVE
  Uterine atony is a leading cause of postpartum hemorrhage. Although most cases of postpartum hemorrhage respond to first-line therapy with uterine massage and oxytocin administration, second-line uterotonics including methylergonovine and carboprost are integral for the management of refractory uterine atony. Despite their ubiquitous use, it is uncertain whether the risk of hemorrhage-related morbidity differs in women exposed to methylergonovine or carboprost at cesarean delivery.
  
  
  METHODS
  We performed a secondary analysis using the Maternal-Fetal Medicine Units Network Cesarean Registry. We identified women who underwent cesarean delivery and received either methylergonovine or carboprost for refractory uterine atony. The primary outcome was hemorrhage-related morbidity defined as intraoperative or postoperative red blood cell transfusion or the need for additional surgical interventions including uterine artery ligation, hypogastric artery ligation, or peripartum hysterectomy for atony. We compared the risk of hemorrhage-related morbidity in those exposed to methylergonovine vs carboprost. Propensity-score matching was used to account for potential confounders.
  
  
  RESULTS
  The study cohort comprised 1335 women; 870 (65.2%) women received methylergonovine and 465 (34.8%) women received carboprost. After accounting for potential confounders, the risk of hemorrhage-related morbidity was higher in the carboprost group than the methylergonovine group (relative risk, 1.7; 95% confidence interval, 1.2-2.6).
  
  
  CONCLUSIONS
  In this propensity score-matched analysis, methylergonovine was associated with reduced risk of hemorrhage-related morbidity during cesarean delivery compared to carboprost. Based on these results, methylergonovine may be a more effective second-line uterotonic.
authors.affiliation: Department of Anesthesia, Stanford University School of Medicine, Stanford, CA. Electronic address: ajbut@stanford.edu.
authors.forename: Alexander J
authors.initials: AJ
authors.lastname: Butwick
authors.affiliation: Department of Anesthesia, Stanford University School of Medicine, Stanford, CA.
authors.forename: Brendan
authors.initials: B
authors.lastname: Carvalho
authors.affiliation: Department of Obstetrics and Gynecology, Stanford University School of Medicine, Stanford, CA.
authors.forename: Yair J
authors.initials: YJ
authors.lastname: Blumenfeld
authors.affiliation: Department of Obstetrics and Gynecology, Stanford University School of Medicine, Stanford, CA.
authors.forename: Yasser Y
authors.initials: YY
authors.lastname: El-Sayed
authors.affiliation: Department of Health Research Policy, Stanford University School of Medicine, Stanford, CA.
authors.forename: Lorene M
authors.initials: LM
authors.lastname: Nelson
authors.affiliation: Division of Pharmacoepidemiology and Pharmacoeconomics, Department of Medicine, Brigham and Women's Hospital, Department of Anesthesiology, Critical Care Medicine, and Pain Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA.
authors.forename: Brian T
authors.initials: BT
authors.lastname: Bateman
mesh_terms: D000328:Adult; D002260:Carboprost / Q000627:therapeutic use*; D002585:Cesarean Section; D015331:Cohort Studies; D017707:Erythrocyte Transfusion / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D007044:Hysterectomy; D008026:Ligation; D008755:Methylergonovine / Q000627:therapeutic use*; D010120:Oxytocics / Q000627:therapeutic use*; D006473:Postpartum Hemorrhage / Q000628:therapy*; D011247:Pregnancy; D057216:Propensity Score; D012307:Risk Factors; D055988:Uterine Artery / Q000601:surgery*; D014593:Uterine Inertia / Q000628:therapy*; D055815:Young Adult
chemical_list: D010120:Oxytocics; D002260:Carboprost; D008755:Methylergonovine
keywords: cesarean delivery; hemorrhage; morbidity; uterine atony