title: Effects of oral and transvaginal ethinyl estradiol on hemostatic factors and hepatic proteins in a randomized, crossover study.
abstract: BACKGROUND
  The use of combined hormonal contraceptives with ethinyl estradiol (EE) and a progestin results in alterations in potential biomarkers of venous thromboembolism risk. Evaluation of the impact of delivery route on these changes is difficult due to an interaction between EE and the progestin component.
  
  
  OBJECTIVE
  The aim of the study was to compare the impact of oral and vaginal administration of EE alone on hemostatic variables and estrogen-sensitive liver proteins.
  
  
  METHODS
  This was a single-center, randomized, crossover study with two treatment cycles separated by a washout cycle.
  
  
  METHODS
  The study was conducted in an academic outpatient center.
  
  
  METHODS
  Fourteen healthy postmenopausal women were enrolled; 13 completed the study and were included in the analyses.
  
  
  METHODS
  Participants were randomized to receive EE (15 microg/d) delivered by oral tablet or vaginal ring for 21 d in one of two treatment sequences.
  
  
  METHODS
  Changes in plasma concentration or activity of 10 hemostatic variables and six estrogen-sensitive liver proteins between baseline and d 21 of treatment were the primary outcomes.
  
  
  RESULTS
  Prothrombin fragment 1 + 2 plasma level was unaffected by treatment or delivery route. Angiotensinogen (expressed as plasma level of angiotensin I) increased similarly with oral and vaginal delivery; mean (sd) increases were 2757 (1033) and 2864 (893) ng /ml, respectively (P = 0.0002). Alterations in other study variables, except total cholesterol, were similar with oral and vaginal administration.
  
  
  CONCLUSIONS
  Our results provide evidence that the customary effects of combined hormonal contraceptives on hemostatic variables and estrogen-sensitive liver proteins are largely related to EE and independent of delivery route during short-term treatment.
authors: Center for Biomedical Research, Population Council, New York, NY 10021, USA. regine@popcbr.rockefeller.edu
authors: Régine
authors: R
authors: Sitruk-Ware
authors: Geneviève
authors: G
authors: Plu-Bureau
authors: Joël
authors: J
authors: Menard
authors: Jacqueline
authors: J
authors: Conard
authors: Sushma
authors: S
authors: Kumar
authors: Jean-Christophe
authors: JC
authors: Thalabard
authors: Barbara
authors: B
authors: Tokay
authors: Philippe
authors: P
authors: Bouchard
mesh_terms: D000282:Administration, Intravaginal; D000284:Administration, Oral; D018592:Cross-Over Studies; D015914:Estrogen Replacement Therapy / Q000379:methods*; D004967:Estrogens / Q000008:administration & dosage* / Q000009:adverse effects; D004997:Ethinyl Estradiol / Q000008:administration & dosage* / Q000009:adverse effects; D005260:Female; D006487:Hemostasis / Q000187:drug effects*; D006801:Humans; D008099:Liver / Q000187:drug effects; D008875:Middle Aged; D012307:Risk Factors; D020246:Venous Thrombosis / Q000139:chemically induced / Q000453:epidemiology
chemical_list: D004967:Estrogens; D004997:Ethinyl Estradiol