title: Prospective study of exogenous hormones and risk of pulmonary embolism in women.
abstract: BACKGROUND
  Current use of oral contraceptives (OCs) is a well-recognised risk factor for venous thrombosis and consequent pulmonary embolism (PE). Little is known about residual effects of past OC use. Furthermore, few epidemiological studies have assessed the relation between postmenopausal use of hormones and thrombotic disease.
  
  
  METHODS
  In this prospective study information was obtained through questionnaires sent every 2 years (1976-92) to 1125,93 women aged 30-55 in 1976. We excluded women with previously diagnosed cardiovascular disease or cancer in 1976 and at the beginning of each subsequent 2-year follow-up period.
  
  
  RESULTS
  From self-reports and medical records, we documented 123 cases of primary PE (no identified antecedent cancer, trauma, surgery, or immobilisation). Current users of postmenopausal hormones had an increased risk of primary PE (relative risk adjusted for multiple risk factors 2.1 [95% CI 1.2-3.8]). However, past use showed no relation to PE (1.3 [0.7-2.4]). In current users of OCs the risk of primary PE was about twice that in non-users (2.2 [0.8-5.9]), but this finding was based on only five cases who were current OC users. Users of OCs in the past had no increase in risk of PE (0.8 [0.5-1.2]). These relations were consistent irrespective of cigarette-smoking status.
  
  
  CONCLUSIONS
  Primary PE was uncommon in this cohort. The risk was increased by current though not past use of postmenopausal hormones or OCs.
authors.affiliation: Channing Laboratory, Boston, MA 02115, USA.
authors.forename: F
authors.initials: F
authors.lastname: Grodstein
authors.forename: M J
authors.initials: MJ
authors.lastname: Stampfer
authors.forename: S Z
authors.initials: SZ
authors.lastname: Goldhaber
authors.forename: J E
authors.initials: JE
authors.lastname: Manson
authors.forename: G A
authors.initials: GA
authors.lastname: Colditz
authors.forename: F E
authors.initials: FE
authors.lastname: Speizer
authors.forename: W C
authors.initials: WC
authors.lastname: Willett
authors.forename: C H
authors.initials: CH
authors.lastname: Hennekens
mesh_terms: D000328:Adult; D015331:Cohort Studies; D003276:Contraceptives, Oral / Q000009:adverse effects*; D015914:Estrogen Replacement Therapy / Q000009:adverse effects*; D004967:Estrogens / Q000008:administration & dosage / Q000009:adverse effects*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D008875:Middle Aged; D015999:Multivariate Analysis; D017698:Postmenopause; D016016:Proportional Hazards Models; D011446:Prospective Studies; D011655:Pulmonary Embolism / Q000139:chemically induced*; D012307:Risk Factors; D012907:Smoking; D013924:Thrombophlebitis / Q000139:chemically induced
chemical_list: D003276:Contraceptives, Oral; D004967:Estrogens