title: Influence of maternal tobacco smoking during pregnancy on uterine, umbilical and fetal cerebral artery blood flows.
abstract: BACKGROUND
  Cigarette smoking during pregnancy is a major cause of adverse perinatal outcome but effects on critical fetal and maternal circulations remain unclear.
  
  
  OBJECTIVE
  To determine (1) the influence of habitual maternal cigarette smoking on blood flow velocities in uterine, umbilical and fetal middle cerebral arteries, and (2) the time-course of changes in these flows after smoking a cigarette.
  
  
  METHODS
  In 74 women who smoked and 69 non-smoking controls we measured Doppler blood flow velocity waveforms in the uterine, umbilical and fetal middle cerebral (MCA) arteries; smokers were divided into light (<10 cigarettes/day, n=28) and heavy smokers (>10 cigarettes/day, n=45).
  
  
  RESULTS
  In the uterine artery there was no significant difference between the systolic/diastolic (S/D) ratio in smoking and non-smoking women; however, in smokers, a diastolic notch was more frequently observed in the uterine artery waveform than in controls (p<0.05), suggestive of a greater resistance in the uterine vasculature. In the umbilical artery, the S/D ratio was significantly greater in smokers than in non-smokers. In the fetal MCA, the S/D ratio was higher in heavy smokers than in light smokers (p<0.05) indicative of greater cerebrovascular resistance. There were no significant correlations between the interval between smoking the last cigarette and making the Doppler measurements and the S/D ratios in any of the vessels.
  
  
  CONCLUSIONS
  Maternal cigarette smoking is associated with evidence of chronically increased resistances in the uterine, umbilical and fetal middle cerebral arteries.
authors.affiliation: Center for Perinatal Medicine, Deaconess Medical Center, Spokane, WA, USA.
authors.forename: Cheryl A
authors.initials: CA
authors.lastname: Albuquerque
authors.forename: Karen R
authors.initials: KR
authors.lastname: Smith
authors.forename: Cherie
authors.initials: C
authors.lastname: Johnson
authors.forename: Rex
authors.initials: R
authors.lastname: Chao
authors.forename: Richard
authors.initials: R
authors.lastname: Harding
mesh_terms: D000328:Adult; D001783:Blood Flow Velocity / Q000187:drug effects; D002536:Cerebral Arteries / Q000187:drug effects* / Q000502:physiology; D005260:Female; D005333:Fetus / Q000098:blood supply*; D006801:Humans; D008431:Maternal-Fetal Exchange / Q000187:drug effects*; D011247:Pregnancy; D012039:Regional Blood Flow / Q000187:drug effects; D012907:Smoking / Q000009:adverse effects* / Q000503:physiopathology; D013997:Time Factors; D014469:Umbilical Arteries / Q000187:drug effects* / Q000503:physiopathology; D014599:Uterus / Q000098:blood supply*