title: Sidestream smoking is equally as damaging as mainstream smoking on IVF outcomes.
abstract: BACKGROUND
  Cigarette smoking (CS) is a widely recognized health hazard, yet it remains prevalent in society and the effects of environmental tobacco smoke exposure on fertility are unknown. Our objective was to measure the effects of CS on the fertility of mainstream (MS) or sidestream (SS) smoke-exposed women compared to their non-smoking (NS) counterparts.
  
  
  METHODS
  This retrospective study investigated 225 female patients undergoing IVF (n = 97) or ICSI (n = 128). Patients were grouped based on their smoking status for comparison. This included: 39 MS (18 IVF and 21 ICSI); 40 SS (16 IVF and 24 ICSI); and 146 NS (63 IVF and 83 ICSI) women. Fertility treatment outcomes including embryo quality, implantation and pregnancy rate were measured.
  
  
  RESULTS
  No difference in embryo quality between the three groups was observed. However, there was a significant difference in implantation rate (MS = 12.0%, SS = 12.6%, and NS = 25.0%) and pregnancy rate (MS = 19.4%, SS = 20.0%, and NS = 48.3%) per embryo transfer.
  
  
  CONCLUSIONS
  Despite similar embryo quality there was a striking difference in implantation and pregnancy rates of MS and SS smokers when compared with NS. Our data demonstrate that the effects of SS smoking are equally as damaging as MS smoke on fertility.
authors.affiliation: Reproductive Biology Division, Department of Obstetrics and Gynecology, McMaster University, Hamilton, Ontario, Canada. nealm@hhsc.ca
authors.forename: Michael S
authors.initials: MS
authors.lastname: Neal
authors.forename: Edward G
authors.initials: EG
authors.lastname: Hughes
authors.forename: Alison C
authors.initials: AC
authors.lastname: Holloway
authors.forename: Warren G
authors.initials: WG
authors.lastname: Foster
mesh_terms: D010064:Embryo Implantation; D005260:Female; D005307:Fertilization in Vitro / Q000706:statistics & numerical data*; D006801:Humans; D007247:Infertility, Female / Q000453:epidemiology* / Q000628:therapy; D011247:Pregnancy; D011256:Pregnancy Outcome / Q000453:epidemiology*; D015995:Prevalence; D012189:Retrospective Studies; D012907:Smoking / Q000009:adverse effects*; D014028:Tobacco Smoke Pollution / Q000009:adverse effects*
chemical_list: D014028:Tobacco Smoke Pollution