title: Oral contraceptive therapy increases oxidative stress in pre-menopausal women.
abstract: BACKGROUND
  Oral contraceptive therapy (OCT) is associated with an increased risk of deep vein thrombosis, venous thromboembolism and stroke. However, the underlying mechanisms have not yet been elucidated. The objective of this study was to investigate the influence of OCT on blood levels of an oxidative stress maker in pre-menopausal women.
  
  
  METHODS
  Oxidative stress was determined in 87 pre-menopausal healthy women (24 with and 63 without OCT) using a blood assay for reactive oxygen metabolites (by the d-ROMs test). The subjects with OCT received a triphasic preparation consisting of ethinyl estradiol and norethisterone.
  
  
  RESULTS
  Subjects with OCT showed significantly higher d-ROMs levels (median: 380; interquartile range: 328-502 Carr U) than those without OCT (325 [271-369]; P < 0.05). The results remained the same after adjusting for potential confounders.
  
  
  CONCLUSIONS
  The use of OCT may increase oxidative stress levels, independent of traditional cardiovascular risk factors, in pre-menopausal women, providing new insights to the primary prevention of vascular complications in these subjects.
authors.affiliation: Jui-Tung Chen Clinic, Tokyo, Japan.
authors.forename: Jui Tung
authors.initials: JT
authors.lastname: Chen
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Kotani