title: Metabolic profile of a continuous versus a cyclic low-dose combined oral contraceptive after one year of use.
abstract: OBJECTIVE
  To compare the effects of a combined oral contraceptive (COC) taken continuously with those of one of similar composition taken cyclically on 30 variables related to haemostasis, lipids, carbohydrates, bone metabolism, and sex hormone-binding globulin (SHBG).
  
  
  METHODS
  Randomised, open-label, multicentre, comparative substudy of a larger phase 3 trial involving 147 healthy women (age 18-49 years). Participants received the COC either continuously (levonorgestrel [LNG] 90 μg/ethinylestradiol [EE] 20 μg) or cyclically (21/7 days pattern; LNG 100 μg/EE 20 μg).
  
  
  RESULTS
  After 13 pill packs, changes in total cholesterol (+0.23 vs. -0.06 mmol/l), low-density lipoprotein cholesterol (+0.25 vs. -0.12 mmol/l), and high-density lipoprotein cholesterol(3) (-0.06 vs. -0.15 mmol/l) differed significantly (p<0.05) between the continuous and cyclic regimens, respectively. Increases were significantly greater (p <0.05) for protein C antigen (+11.8% vs. +6.1%) and SHBG (+791 vs. +565 nmol/l), and significantly smaller (p <0.05, ranks) for D-dimer (+19 vs. +37 μg FE/l).
  
  
  CONCLUSIONS
  Overall, the continuous and cyclic regimens affected metabolic variables similarly. The larger increase in SHBG with the continuous COC is consistent with a higher net oestrogenic effect due to a lower daily dose of LNG. Prospective studies are required to determine the long-term effects of this continuous COC regimen.
authors.affiliation: Centre for Human Drug Research, Leiden, The Netherlands.
authors.forename: Mandana
authors.initials: M
authors.lastname: Rad
authors.forename: Cornelis
authors.initials: C
authors.lastname: Kluft
authors.forename: Marieke L
authors.initials: ML
authors.lastname: de Kam
authors.forename: Piet
authors.initials: P
authors.lastname: Meijer
authors.forename: Adam F
authors.initials: AF
authors.lastname: Cohen
authors.forename: Gary S
authors.initials: GS
authors.lastname: Grubb
authors.forename: Ginger D
authors.initials: GD
authors.lastname: Constantine
authors.forename: Jacobus
authors.initials: J
authors.lastname: Burggraaf
mesh_terms: D000328:Adult; D016723:Bone Remodeling / Q000187:drug effects*; D002784:Cholesterol / Q000097:blood; D008076:Cholesterol, HDL / Q000097:blood; D008078:Cholesterol, LDL / Q000097:blood; D003277:Contraceptives, Oral, Combined / Q000008:administration & dosage*; D004305:Dose-Response Relationship, Drug; D004334:Drug Administration Schedule; D004997:Ethinyl Estradiol / Q000008:administration & dosage*; D005260:Female; D006801:Humans; D016912:Levonorgestrel / Q000008:administration & dosage*; D008055:Lipids / Q000097:blood*; D008875:Middle Aged; D012738:Sex Hormone-Binding Globulin / Q000187:drug effects*; D014280:Triglycerides / Q000097:blood; D016387:Women's Health; D055815:Young Adult
chemical_list: D008076:Cholesterol, HDL; D008078:Cholesterol, LDL; D003277:Contraceptives, Oral, Combined; D008055:Lipids; D012738:Sex Hormone-Binding Globulin; D014280:Triglycerides; D004997:Ethinyl Estradiol; D016912:Levonorgestrel; D002784:Cholesterol