title: Influence of pregnancy and smoking on brachial artery flow-mediated dilation values and time until maximum response.
abstract: OBJECTIVE
  To evaluate the effect of pregnancy and smoking on endothelial function using brachial artery flow-mediated dilation (FMD) and to determine the time necessary until the occurrence of maximum brachial artery dilation after stimulus.
  
  
  METHODS
  This study was an observational study evaluating 133 women, who were grouped as follows: non-smoking pregnant women (N = 47), smoking pregnant women (N = 33), non-smoking women (N = 34), and smoking pregnant women (N = 19). The diameter of the brachial artery was measured at baseline and at 30, 60, 90 and 120 s after stimulus. The relative change of brachial artery was determined for each of these four moments. FMD measured at 60 s after stimulus was compared between the groups.
  
  
  RESULTS
  The maximum FMD was observed at 60 s after cuff release in all groups. FMD was greater among non-smoking pregnant women compared to smoking pregnant women (11.50 ± 5.77 vs. 8.74 ± 4.83; p = 0.03) and also between non-smoking non-pregnant women compared to smoking non-pregnant women (10.52 ± 4.76 vs. 7.21 ± 5.57; p = 0.03).
  
  
  CONCLUSIONS
  Maximum FMD was observed approximately 60 s after stimulus in all groups regardless of smoking and pregnancy status. The smoking habit seems to lead to endothelial dysfunction both in pregnant and non-pregnant women, as demonstrated by the lower FMD in smokers.
authors.affiliation: Escola de Ultra-sonografia e Reciclagem Médica de Ribeirão Preto, Ribeirão Prêto, São Paulo, Brazil.
authors.forename: Luis G C
authors.initials: LG
authors.lastname: Nicolau
authors.forename: Wellington P
authors.initials: WP
authors.lastname: Martins
authors.forename: Francisco M P
authors.initials: FM
authors.lastname: Gallarreta
authors.forename: Jailson C
authors.initials: JC
authors.lastname: Lima
authors.forename: Francisco Mauad
authors.initials: FM
authors.lastname: Filho
mesh_terms: D000328:Adult; D001916:Brachial Artery / Q000000981:diagnostic imaging / Q000503:physiopathology*; D004730:Endothelium, Vascular / Q000000981:diagnostic imaging / Q000502:physiology*; D005260:Female; D006801:Humans; D008875:Middle Aged; D010991:Plethysmography; D011247:Pregnancy / Q000502:physiology*; D012907:Smoking / Q000503:physiopathology*; D013997:Time Factors; D014111:Tourniquets; D014463:Ultrasonography; D014664:Vasodilation / Q000502:physiology*