title: Smoking ban and small-for-gestational age births in Ireland.
abstract: BACKGROUND
  Ireland introduced a comprehensive workplace smoke-free legislation in March, 2004. Smoking-related adverse birth outcomes have both health care and societal cost implications. The main aim of this study was to determine the impact of the Irish smoke-free legislation on small-for-gestationa- age (SGA) births.
  
  
  RESULTS
  We developed a population-based birthweight (BW) percentile curve based on a recent study to compute SGA (BW <5(th) percentile) and very SGA (vSGA - BW<3(rd) percentile) for each gestational week. Monthly births born between January 1999 and December 2008 were analyzed linking with monthly maternal smoking rates from a large referral maternity university hospital. We ran individual control and CUSUM charts, with bootstrap simulations, to pinpoint the breakpoint for the impact of ban implementation ( = April 2004). Monthly SGA rates (%) before and after April 2004 was considered pre and post ban period births, respectively. Autocorrelation was tested using Durbin Watson (DW) statistic. Mixed models using a random intercept and a fixed effect were employed using SAS (v 9.2). A total of 588,997 singleton live-births born between January 1999 and December 2008 were analyzed. vSGA and SGA monthly rates declined from an average of 4.7% to 4.3% and from 6.9% to 6.6% before and after April 2004, respectively. No auto-correlation was detected (DW = ~2). Adjusted mixed models indicated a significant decline in both vSGA and SGA rates immediately after the ban [(-5.3%; 95% CI -5.43% to -5.17%, p<0.0001) and (-0.45%; 95% CI: -0.7% to -0.19%, p<0.0007)], respectively. Significant gradual effects continued post the ban periods for vSGA and SGA rates, namely, -0.6% (p<0.0001) and -0.02% (p<0.0001), respectively.
  
  
  CONCLUSIONS
  A significant reduction in small-for-gestational birth rates both immediately and sustained over the post-ban period, reinforces the mounting evidence of the positive health effect of a successful comprehensive smoke-free legislation in a vulnerable population group as pregnant women.
authors.affiliation: TobaccoFree Research Institute Ireland, Dublin, Ireland. z.kabir@ucc.ie
authors.forename: Zubair
authors.initials: Z
authors.lastname: Kabir
authors.forename: Sean
authors.initials: S
authors.lastname: Daly
authors.forename: Vanessa
authors.initials: V
authors.lastname: Clarke
authors.forename: Sheila
authors.initials: S
authors.lastname: Keogan
authors.forename: Luke
authors.initials: L
authors.lastname: Clancy
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D007236:Infant, Small for Gestational Age; D007494:Ireland / Q000453:epidemiology; D008954:Models, Biological; D036801:Parturition; D011247:Pregnancy; D012189:Retrospective Studies; D061845:Smoke-Free Policy; D012907:Smoking / Q000009:adverse effects / Q000453:epidemiology
references.citation: BMJ. 2005 Nov 12;331(7525):1117
references.pmid: 16230313
references.citation: Nicotine Tob Res. 2010 Feb;12(2):127-35
references.pmid: 20038509
references.citation: Lancet. 2011 May 28;377(9780):1855-61
references.pmid: 21621717
references.citation: Pediatrics. 2010 Apr;125(4):721-8
references.pmid: 20211945
references.citation: BMC Pregnancy Childbirth. 2010 Jul 09;10:36
references.pmid: 20618921
references.citation: PLoS Med. 2012;9(3):e1001175
references.pmid: 22412353
references.citation: BJOG. 2009 Dec;116(13):1782-7
references.pmid: 19832830
references.citation: IARC Monogr Eval Carcinog Risks Hum. 2004;83:1-1438
references.pmid: 15285078
references.citation: Nicotine Tob Res. 2004 Apr;6 Suppl 2:S125-40
references.pmid: 15203816
references.citation: J Womens Health (Larchmt). 2012 Jun;21(6):621-7
references.pmid: 22401497
references.citation: Arch Dis Child. 2010 Jan;95(1):42-5
references.pmid: 19843508
references.citation: Ir Med J. 2012 Apr;105(4):105-8
references.pmid: 22708221
references.citation: Lancet. 1992 Feb 1;339(8788):283-7
references.pmid: 1346292
references.citation: BMJ. 2009 Oct 29;339:b4347
references.pmid: 19875845
references.citation: Am J Respir Crit Care Med. 2007 Apr 15;175(8):840-5
references.pmid: 17204724
references.citation: Am J Public Health. 1994 Jul;84(7):1127-31
references.pmid: 8017537
references.citation: JAMA. 2010 Feb 10;303(6):527-34
references.pmid: 20145229
references.citation: Lancet. 1999 Jul 24;354(9175):303
references.pmid: 10440311
references.citation: Expert Rev Obstet Gynecol. 2008 Nov 1;3(6):719-730
references.pmid: 19881889
references.citation: Tob Control. 2013 May;22(e1):e2-9
references.pmid: 22331456
references.citation: BMC Pregnancy Childbirth. 2008 Feb 25;8:5
references.pmid: 18298810
references.citation: Acta Obstet Gynecol Scand. 2010;89(4):423-441
references.pmid: 20085532
references.citation: Swiss Med Wkly. 2005 Sep 3;135(35-36):525-30
references.pmid: 16323070
references.citation: N Engl J Med. 2008 Jul 31;359(5):482-91
references.pmid: 18669427
references.citation: J Perinat Med. 2008;36(1):70-2
references.pmid: 18184099
references.citation: J Womens Health (Larchmt). 2012 Jun;21(6):616-8
references.pmid: 22680609
references.citation: Early Hum Dev. 2007 Aug;83(8):491-5
references.pmid: 17079098