title: The effect of cigarette smoking during pregnancy on mode of delivery in uncomplicated term singleton pregnancies.
abstract: OBJECTIVE
  To examine the influence of cigarette smoking during pregnancy on mode of delivery.
  
  
  METHODS
  A retrospective analysis of 6105 uncomplicated term singleton pregnancies for mode of delivery was performed with respect to smoking status.
  
  
  RESULTS
  Of all, 680 (84.0%) smokers and 4588 (86.7%) non-smokers had a spontaneous vaginal delivery, 65 (8.0%) smokers and 393 (7.4%) non-smokers had an instrumental delivery and 65 (8.0%) smokers and 314 (5.9%) non-smokers had a cesarean delivery (p = 0.051). Smoking during pregnancy increased the risk of any operative or instrumental intervention by OR 1.240, 95% CI 1.012-1.523. Non-reassuring fetal heart rate pattern that warranted either cesarean or instrumental intervention was present in 99 (12.2%) out of 810 smokers and in 392 out of 5295 (7.4%) non-smokers, p < 0.001). Smoking during pregnancy increased the risk of non-reassuring fetal heart rate pattern that warranted either cesarean or instrumental intervention by OR 1.650 (95% CI 1.341-2.022).
  
  
  CONCLUSIONS
  Women with uncomplicated term singleton pregnancies who smoke during pregnancy are at an increased risk of fetal compromise during labor (as judged by non-reassuring fetal heart rate pattern), leading to increased rates of operative delivery (cesarean either instrumental).
authors.affiliation: Department of Obstetrics and Gynecology, Edith Wolfson Medical Center , Holon , Israel .
authors.forename: Samuel
authors.initials: S
authors.lastname: Lurie
authors.forename: Shay
authors.initials: S
authors.lastname: Ribenzaft
authors.forename: Mona
authors.initials: M
authors.lastname: Boaz
authors.forename: Abraham
authors.initials: A
authors.lastname: Golan
authors.forename: Oscar
authors.initials: O
authors.lastname: Sadan
mesh_terms: D000328:Adult; D001724:Birth Weight; D002585:Cesarean Section / Q000706:statistics & numerical data; D036861:Delivery, Obstetric / Q000295:instrumentation / Q000379:methods* / Q000706:statistics & numerical data*; D005260:Female; D005316:Fetal Distress / Q000453:epidemiology; D006340:Heart Rate, Fetal; D006801:Humans; D007231:Infant, Newborn; D007744:Obstetric Labor Complications / Q000453:epidemiology / Q000209:etiology; D011247:Pregnancy; D012189:Retrospective Studies; D012907:Smoking / Q000009:adverse effects / Q000453:epidemiology*; D047929:Term Birth; D055815:Young Adult