title: Neonatal opioid withdrawal and antenatal opioid prescribing.
abstract: BACKGROUND
  The incidence of neonatal opioid withdrawal is increasing in both Canada and the United States. However, the degree to which the treatment of pain with opioids, rather than the misuse of prescription opioids or heroin, contributes to the prevalence of neonatal opioid withdrawal remains unknown.
  
  
  METHODS
  We conducted a retrospective, population-based, cross-sectional study between 1992 and 2011 in Ontario with 2 objectives. First, we determined the annual incidence of neonatal abstinence syndrome. Second, using data from a subset of women eligible for publicly funded prescription drugs, we determined what proportion of women who deliver an infant with neonatal abstinence syndrome were given a prescription for an opioid before and during pregnancy.
  
  
  RESULTS
  The incidence of neonatal abstinence syndrome in Ontario increased 15-fold during the study period, from 0.28 per 1000 live births in 1992 to 4.29 per 1000 live births in 2011. During the final 5 years of the study, we identified 927 deliveries of infants with neonatal abstinence syndrome to mothers who were public drug plan beneficiaries. Of these mothers, 67% had received an opioid prescription in the 100 days preceding delivery, including 53.3% who received methadone, an increase from 28.6% in the interval spanning 1 to 2 years before delivery (p < 0.001). Prescription for nonmethadone opioids decreased from 38% to 17% (p < 0.001).
  
  
  CONCLUSIONS
  The incidence of neonatal opioid withdrawal in Ontario has increased substantially over the last 20 years. Most of the women in this cohort who delivered an infant with neonatal abstinence syndrome had received a prescription for an opioid both before and during their pregnancy.
authors.affiliation: Department of Family and Community Medicine, St. Michael's Hospital.
authors.forename: Suzanne D
authors.initials: SD
authors.lastname: Turner
authors.affiliation: Li KaShing Knowledge Institute, St. Michael's Hospital ; Leslie Dan Faculty of Pharmacy, University of Toronto.
authors.forename: Tara
authors.initials: T
authors.lastname: Gomes
authors.affiliation: Institute for Clinical Evaluative Sciences.
authors.forename: Ximena
authors.initials: X
authors.lastname: Camacho
authors.affiliation: Institute for Clinical Evaluative Sciences.
authors.forename: Zhan
authors.initials: Z
authors.lastname: Yao
authors.affiliation: Institute for Clinical Evaluative Sciences ; Division of Paediatric Medicine, Hospital for Sick Children ; Institute of Health Policy, Management and Evaluation, University of Toronto.
authors.forename: Astrid
authors.initials: A
authors.lastname: Guttmann
authors.affiliation: Li KaShing Knowledge Institute, St. Michael's Hospital ; Leslie Dan Faculty of Pharmacy, University of Toronto.
authors.forename: Muhammad M
authors.initials: MM
authors.lastname: Mamdani
authors.affiliation: Institute for Clinical Evaluative Sciences ; Department of Medicine, University of Toronto ; Sunnybrook Research Institute, Toronto, Ont.
authors.forename: David N
authors.initials: DN
authors.lastname: Juurlink
authors.affiliation: Institute for Clinical Evaluative Sciences ; Department of Medicine, University of Toronto ; Department of Medicine, St. Michael's Hospital.
authors.forename: Irfan A
authors.initials: IA
authors.lastname: Dhalla
references.citation: Addiction. 1998 Jul;93(7):1033-42
references.pmid: 9744134
references.citation: JAMA. 2012 May 9;307(18):1934-40
references.pmid: 22546608
references.citation: Arch Intern Med. 2011 Apr 11;171(7):686-91
references.pmid: 21482846
references.citation: Can Fam Physician. 2009 Jan;55(1):68-9, 69.e1-5
references.pmid: 19155373
references.citation: Drug Alcohol Rev. 2007 Sep;26(5):487-92
references.pmid: 17701511
references.citation: Curr Opin Pediatr. 2012 Apr;24(2):252-8
references.pmid: 22227786
references.citation: Am J Obstet Gynecol. 2011 Mar;204(3):259.e1-4
references.pmid: 21376165
references.citation: J Popul Ther Clin Pharmacol. 2012;19(3):e488-506
references.pmid: 23241498
references.citation: CMAJ. 2009 Dec 8;181(12):891-6
references.pmid: 19969578
references.citation: Obstet Gynecol. 2012 May;119(5):924-33
references.pmid: 22525903
references.citation: Pediatrics. 2012 Jun;129(6):e1421-30
references.pmid: 22585770
references.citation: N Engl J Med. 2010 Nov 18;363(21):1981-5
references.pmid: 21083382
references.citation: Can Fam Physician. 2007 Oct;53(10):1722-30
references.pmid: 17934036
references.citation: Ambul Pediatr. 2008 May-Jun;8(3):205-9
references.pmid: 18501869
references.citation: Pediatrics. 2012 Feb;129(2):e540-60
references.pmid: 22291123
references.citation: JAMA. 2012 May 9;307(18):1974-5
references.pmid: 22546607
references.citation: Clin Toxicol (Phila). 2012 Jun;50(5):390-5
references.pmid: 22537257
references.citation: Arch Dis Child. 1988 Jan;63(1):81-3
references.pmid: 3348657
references.citation: Eur J Pediatr. 1998 Sep;157(9):724-30
references.pmid: 9776530
references.citation: Early Hum Dev. 1977 Oct;1(2):159-69
references.pmid: 617308
references.citation: BMJ. 2013 May 23;346:f2610
references.pmid: 23704171
references.citation: Ann Intern Med. 2013 Mar 19;158(6):447-55
references.pmid: 23552325