JANUARY JOGC JANVIER 2014 l 21 OBSTETRICS Key Words: Postpartum hemorrhage, atonic postpartum hemorrhage, uterine atony, maternal morbidity Competing Interests: None declared. Received on May 27, 2013 Accepted on August 6, 2013 Temporal Trends in Postpartum Hemorrhage and Severe Postpartum Hemorrhage in Canada From 2003 to 2010 Azar Mehrabadi, MSc, 1 Shiliang Liu, MD, PhD, 2 Sharon Bartholomew, MHSc, 2 Jennifer A. Hutcheon, PhD, 1 Michael S. Kramer, MD, 3 Robert M. Liston, MB, 4 K.S. Joseph, MD, PhD 1 ; for the Maternal Health Study Group of the Canadian Perinatal Surveillance System (Public Health Agency of Canada) 1 Department of Obstetrics and Gynaecology, and the School of Population and Public Health, University of British Columbia, and the Children’s and Women’s Hospital and Health Centre of British Columbia, Vancouver BC 2 Maternal and Infant Health Section, Public Health Agency of Canada, Ottawa ON 3 Departments of Pediatrics, and of Epidemiology, Biostatistics and Occupational Health, McGill University, Montreal QC 4 Department of Obstetrics and Gynaecology, University of British Columbia, and the Children’s and Women’s Hospital and Health Centre of British Columbia, Vancouver BC Abstract Objective: Increases in postpartum hemorrhage have been reported from several countries. We assessed temporal trends in postpartum hemorrhage and severe postpartum hemorrhage in Canada between 2003 and 2010. Methods: We carried out a population-based cohort study of all hospital deliveries in Canada (excluding Quebec) from 2003 to 2010 (n = 2 193 425), using data from the Canadian Institute for Health Information. Postpartum hemorrhage was deined as a blood loss of ≥ 500 mL following vaginal delivery or ≥ 1000 mL following Caesarean section, or as noted by the care provider. Severe postpartum hemorrhage was deined as postpartum hemorrhage plus blood transfusion, hysterectomy, or other procedures to control bleeding (including uterine suturing or ligation/embolization of pelvic arteries). Temporal trends were assessed using the chi-square test for trend, relative risks, and logistic regression. Results: Postpartum hemorrhage increased by 22% (95% CI 20% to 25%) from 5.1% in 2003 to 6.2% in 2010 (P < 0.001), driven by a 29% increase (95% CI 26% to 33%) in atonic postpartum hemorrhage (3.9% in 2003 vs. 5.0% in 2010, P < 0.001). Postpartum hemorrhage with blood transfusion increased from 36.7 to 50.4 per 10 000 deliveries (P < 0.001), while postpartum hemorrhage with hysterectomy increased from 4.9 to 5.8 per 10 000 deliveries (P < 0.01). Postpartum hemorrhage with uterine suturing, or ligation/embolization of pelvic arteries, increased from 4.1 to 10.7 per 10 000 deliveries (P < 0.001). These increases occurred in most provinces and territories, and could not be explained by changes in maternal, fetal, and obstetric factors. Conclusion: Rates of postpartum hemorrhage and severe postpartum hemorrhage continued to increase in Canada between 2003 and 2010. Résumé Objectif : Une hausse des taux d’hémorragie postpartum a été signalée dans plusieurs pays. Nous avons évalué les tendances temporelles en matière d’hémorragie postpartum et d’hémorragie postpartum grave au Canada pour la période se situant entre 2003 et 2010. Méthodes : Nous avons mené une étude de cohorte en population générale ayant porté sur tous les accouchements hospitaliers au Canada (exception faite du Québec) pour la période se situant entre 2003 et 2010 (n = 2 193 425), au moyen des données issues de l’Institut canadien d’information sur la santé. L’hémorragie postpartum a été déinie comme étant une perte sanguine ≥ 500 ml à la suite d’un accouchement vaginal ou ≥ 1 000 ml à la suite d’une césarienne, ou encore conformément aux notes du fournisseur de soins. L’hémorragie postpartum grave a été déinie comme étant une hémorragie postpartum s’accompagnant d’une transfusion sanguine, d’une hystérectomie ou d’autres interventions visant à juguler les saignements (y compris les sutures utérines ou la ligature / l’embolisation des artères pelviennes). Les tendances temporelles ont été évaluées au moyen d’un test du chi carré (pour ce qui est de l’évolution), des risques relatifs et d’une régression logistique. Résultats : Le taux d’hémorragie postpartum a connu une hausse de 22 % (IC à 95 %, 20 % - 25 %), soit de 5,1 % en 2003 à 6,2 % en