title: Trends in optimal, suboptimal, and questionably appropriate receipt of antenatal corticosteroid prophylaxis.
abstract: OBJECTIVE
  To conduct a population-based study to assess rates of optimal, suboptimal, and questionably appropriate administration of antenatal corticosteroid (betamethasone or dexamethasone) use.
  
  
  METHODS
  All live births in Nova Scotia, Canada, from 1988 to 2012 were included in the study. Temporal trends in optimal (proportion of live births at 24-34 weeks of gestation exposed to antenatal corticosteroids between 24 hours and 7 days before delivery), suboptimal (proportion of live births at 24-34 weeks of gestation exposed to antenatal corticosteroids less than 24 hours or more than 7 days before delivery), and questionably appropriate exposure to antenatal corticosteroids (proportion of live births 35 weeks of gestation or greater exposed to antenatal corticosteroids) were quantified using odds ratios (ORs) and 95% confidence intervals (CIs).
  
  
  RESULTS
  Among 246,459 live births between 1988 and 2012, 2.5% received a partial or a full course of antenatal corticosteroids. The rate of antenatal corticosteroid exposure for neonates born between 28 and 32 weeks of gestation increased from 39.5% in 1988-1992 to 79.3% in 2008-2012, whereas exposure for those born at 33-34 weeks of gestation increased from 14.3 to 49.7%. Optimal antenatal corticosteroid receipt increased from 10% in 1988 to 23% in 2012 (OR 2.7, 95% CI 1.6-4.5), suboptimal administration increased from 7 to 34% (OR 6.7, 95% CI 3.9-11.6), and questionably appropriate administration increased from 0.2% in 1988 to 1.7% in 2012 (OR 7.5, 95% CI 4.9-11.3). Of the women who received antenatal corticosteroids in 2012, 52% delivered at 35 weeks of gestation or greater.
  
  
  CONCLUSIONS
  Temporal increases in optimal exposure to antenatal corticosteroids have been matched by increases in suboptimal and questionably appropriate receipt of antenatal corticosteroids, highlighting the need for accurate preterm delivery prognostic models.
authors.affiliation: Department of Obstetrics & Gynaecology and the School of Population and Public Health, University of British Columbia, and the BC Women's Hospital and Health Centre, Vancouver, British Columbia, and the Reproductive Care Program of Nova Scotia and the Department of Obstetrics and Gynaecology, Dalhousie University, Halifax, Nova Scotia, Canada.
authors.forename: Neda
authors.initials: N
authors.lastname: Razaz
authors.forename: Amanda
authors.initials: A
authors.lastname: Skoll
authors.forename: John
authors.initials: J
authors.lastname: Fahey
authors.forename: Victoria M
authors.initials: VM
authors.lastname: Allen
authors.forename: K S
authors.initials: KS
authors.lastname: Joseph
mesh_terms: D000328:Adult; D001623:Betamethasone / Q000008:administration & dosage*; D015331:Cohort Studies; D003907:Dexamethasone / Q000008:administration & dosage*; D005260:Female; D005938:Glucocorticoids / Q000008:administration & dosage*; D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature; D007235:Infant, Premature, Diseases / Q000517:prevention & control*; D011247:Pregnancy; D055815:Young Adult
chemical_list: D005938:Glucocorticoids; D003907:Dexamethasone; D001623:Betamethasone