Increased impact of a contraceptive vaginal ring with ethinyl estradiol and nestorone on C-reactive protein

Steroids. 2012 Nov;77(13):1483-6. doi: 10.1016/j.steroids.2012.08.003. Epub 2012 Sep 8.


OBJECTIVE & STUDY DESIGN: In a parallel design, 23 and 22 healthy pre-menopausal women were randomly administered a contraceptive vaginal ring (CVR) delivering 150/15 μg Nestorone®/ethinyl estradiol (EE) daily or an oral contraceptive (OC) containing levonorgestrel and EE (150/30 μg) for three cycles, to compare the effects on C-reactive protein and other markers of inflammation. ANCOVA was performed with baseline values as covariate.

Results: The CVR caused [estimate of difference (95% CI), 109% (16-275%)] higher levels of CRP than the OC, while no difference was observed for leukocyte 1% (-13/+17%) and monocyte counts 6% (-9/+23%). The greater increase in CRP was confined to CVR recipients exhibiting low pre-treatment CRP-levels, whereas no difference was observed in the increases for recipients in the highest tertile of pre-treatment CRP levels.

Conclusion: The difference in CRP rise in CVR and OC users does not correspond with the effects on other markers of inflammation and is most likely due to a specific difference in the effect of ethinyl-estradiol combined with nestorone in cases with low CRP.

Publication types

  • Randomized Controlled Trial
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Adolescent
  • Adult
  • C-Reactive Protein / metabolism*
  • Contraceptive Devices, Female / adverse effects*
  • Ethinyl Estradiol / administration & dosage
  • Ethinyl Estradiol / adverse effects*
  • Female
  • Humans
  • Norprogesterones / administration & dosage
  • Norprogesterones / adverse effects*
  • Young Adult


  • Norprogesterones
  • Ethinyl Estradiol
  • ST 1435
  • C-Reactive Protein