title: Risk factors for postpartum hemorrhage in vaginal deliveries in a Latin-American population.
abstract: OBJECTIVE
  To identify risk factors for immediate postpartum hemorrhage after vaginal delivery in a South American population.
  
  
  METHODS
  This was a prospective cohort study including all vaginal births (N=11,323) between October and December 2003 and October and December 2005 from 24 maternity units in two South American countries (Argentina and Uruguay). Blood loss was measured in all births using a calibrated receptacle. Moderate postpartum hemorrhage and severe postpartum hemorrhage were defined as blood loss of at least 500 mL and at least 1,000 mL, respectively.
  
  
  RESULTS
  Moderate and severe postpartum hemorrhage occurred in 10.8% and 1.9% of deliveries, respectively. The risk factors more strongly associated and the incidence of moderate postpartum hemorrhage in women with each of these factors were: retained placenta (33.3%) (adjusted odds ratio [OR] 6.02, 95% confidence interval [CI] 3.50-10.36), multiple pregnancy (20.9%) (adjusted OR 4.67, CI 2.41-9.05), macrosomia (18.6%) (adjusted OR 2.36, CI 1.93-2.88), episiotomy (16.2%) (adjusted OR 1.70, CI 1.15-2.50), and need for perineal suture (15.0%) (adjusted OR 1.66, CI 1.11-2.49). Active management of the third stage of labor, multiparity, and low birth weight were found to be protective factors. Severe postpartum hemorrhage was associated with retained placenta (17.1%) (adjusted OR 16.04, CI 7.15-35.99), multiple pregnancy (4.7%) (adjusted OR 4.34, CI 1.46-12.87), macrosomia (4.9%) (adjusted OR 3.48, CI 2.27-5.36), induced labor (3.5%) (adjusted OR 2.00, CI 1.30-3.09), and need for perineal suture (2.5%) (adjusted OR 2.50, CI 1.87-3.36).
  
  
  CONCLUSIONS
  Many of the risk factors for immediate postpartum hemorrhage in this South American population are related to complications of the second and third stage of labor.
  
  
  METHODS
  II.
authors.affiliation: From the Perinatal Research Unit, School of Medicine, University of Uruguay, Montevideo, Uruguay; the Institute of Clinical Effectiveness and Health Policy, Buenos Aires, Argentina; and the School of Public Health and Tropical Medicine, Tulane University, New Orleans. Louisiana.
authors.forename: Claudio G
authors.initials: CG
authors.lastname: Sosa
authors.forename: Fernando
authors.initials: F
authors.lastname: Althabe
authors.forename: José M
authors.initials: JM
authors.lastname: Belizán
authors.forename: Pierre
authors.initials: P
authors.lastname: Buekens
mesh_terms: D000328:Adult; D015331:Cohort Studies; D036861:Delivery, Obstetric; D004841:Episiotomy / Q000009:adverse effects; D005260:Female; D005320:Fetal Macrosomia; D006801:Humans; D007748:Labor Stage, Second; D007749:Labor Stage, Third; D007843:Latin America; D018457:Placenta, Retained; D006473:Postpartum Hemorrhage / Q000209:etiology* / Q000503:physiopathology / Q000517:prevention & control; D011247:Pregnancy; D011272:Pregnancy, Multiple; D011446:Prospective Studies; D012307:Risk Factors; D013537:Sutures