title: Regional differences in severe postpartum hemorrhage: a nationwide comparative study of 1.6 million deliveries.
abstract: BACKGROUND
  The incidence of severe postpartum hemorrhage (PPH) is increasing. Regional variation may be attributed to variation in provision of care, and as such contribute to this increasing incidence. We assessed reasons for regional variation in severe PPH in the Netherlands.
  
  
  METHODS
  We used the Netherlands Perinatal Registry and the Dutch Maternal Mortality Committee to study severe PPH incidences (defined as blood loss ≥ 1000 mL) across both regions and neighborhoods of cities among all deliveries between 2000 and 2008. We first calculated crude incidences. We then used logistic multilevel regression analyses, with hospital or midwife practice as second level to explore further reasons for the regional variation.
  
  
  RESULTS
  We analyzed 1599867 deliveries in which the incidence of severe PPH was 4.5%. Crude incidences of severe PPH varied with factor three between regions while between neighborhoods variation was even larger. We could not explain regional variation by maternal characteristics (age, parity, ethnicity, socioeconomic status), pregnancy characteristics (singleton, gestational age, birth weight, pre-eclampsia, perinatal death), medical interventions (induction of labor, mode of delivery, perineal laceration, placental removal) and health care setting.
  
  
  CONCLUSIONS
  In a nationwide study in The Netherlands, we observed wide practice variation in PPH. This variation could not be explained by maternal characteristics, pregnancy characteristics, medical interventions or health care setting. Regional variation is either unavoidable or subsequent to regional variation of a yet unregistered variable.
authors.affiliation: Department of Obstetrics and Gynecology, Division of Obstetrics & Prenatal Medicine, Erasmus MC, 's-Gravendijkwal 230, 3015, CE Rotterdam, The Netherlands. babette_prick@hotmail.com.|Department of Obstetrics and Gynecology, Maasstad Hospital, Maasstadweg 21, 3079, DZ Rotterdam, the Netherlands. babette_prick@hotmail.com.
authors.forename: Babette W
authors.initials: BW
authors.lastname: Prick
authors.affiliation: Department of Obstetrics, Leiden University Medical Centre, Albinusdreef 2, 2333, ZA Leiden, The Netherlands. jvonschmidt@hotmail.com.
authors.forename: Joost F von Schmidt
authors.initials: JF
authors.lastname: Auf Altenstadt
authors.affiliation: The Netherlands Perinatal Registry, Mercatorlaan 1200, 3528BL, Utrecht, The Netherlands. chukkelhoven@perinatreg.nl.
authors.forename: Chantal W P M
authors.initials: CW
authors.lastname: Hukkelhoven
authors.affiliation: Department of Obstetrics and Gynecology, Division of Obstetrics & Prenatal Medicine, Erasmus MC, 's-Gravendijkwal 230, 3015, CE Rotterdam, The Netherlands. g.bonsel@erasmusmc.nl.
authors.forename: Gouke J
authors.initials: GJ
authors.lastname: Bonsel
authors.affiliation: Department of Obstetrics and Gynecology, Division of Obstetrics & Prenatal Medicine, Erasmus MC, 's-Gravendijkwal 230, 3015, CE Rotterdam, The Netherlands. e.a.p.steegers@erasmusmc.nl.
authors.forename: Eric A P
authors.initials: EA
authors.lastname: Steegers
authors.affiliation: Robinsion Research Institute, School of Pediatrics and Reproductive Health, University of Adelaide, Adelaide, 5000, SA, Australia. ben.mol@adelaide.edu.au.
authors.forename: Ben W
authors.initials: BW
authors.lastname: Mol
authors.affiliation: Department of Obstetrics and Gynecology, Isala Klinieken, Groot Wezenland 20, 8011, JW Zwolle, The Netherlands. jokeschutte@yahoo.com.
authors.forename: Joke M
authors.initials: JM
authors.lastname: Schutte
authors.affiliation: Department of Obstetrics, Leiden University Medical Centre, Albinusdreef 2, 2333, ZA Leiden, The Netherlands. k.w.m.bloemenkamp@lumc.nl.
authors.forename: Kitty W M
authors.initials: KW
authors.lastname: Bloemenkamp
authors.affiliation: Department of Obstetrics and Gynecology, Division of Obstetrics & Prenatal Medicine, Erasmus MC, 's-Gravendijkwal 230, 3015, CE Rotterdam, The Netherlands. j.j.duvekot@erasmusmc.nl.
authors.forename: Johannes J
authors.initials: JJ
authors.lastname: Duvekot
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D001724:Birth Weight; D015331:Cohort Studies; D036861:Delivery, Obstetric / Q000009:adverse effects / Q000379:methods / Q000706:statistics & numerical data; D003710:Demography; D005260:Female; D005865:Gestational Age; D006801:Humans; D015994:Incidence; D008428:Maternal Mortality; D009426:Netherlands / Q000453:epidemiology; D010298:Parity; D006473:Postpartum Hemorrhage / Q000175:diagnosis / Q000401:mortality / Q000628:therapy; D010818:Practice Patterns, Physicians' / Q000706:statistics & numerical data; D011247:Pregnancy; D012307:Risk Factors; D012720:Severity of Illness Index; D012959:Socioeconomic Factors