A comparison between the vaginal ring and oral contraceptives

Obstet Gynecol. 2004 Sep;104(3):555-63. doi: 10.1097/01.AOG.0000136082.59644.13.


Objective: To investigate whether contraceptive vaginal ring use results in similar estimated genital symptoms, signs, examination, and laboratory findings compared with oral contraceptive use.

Methods: Women were randomly assigned to either contraceptive vaginal ring or a 20 microg ethinyl estradiol oral contraceptive pill use for 3 consecutive 28-day cycles, directly followed by 3 cycles of the study drug not initially assigned. Subjects scored genital symptoms on a daily diary using a 0-4 scale and underwent a baseline, cycle 2, cycle 4, and exit pelvic examination including vaginal discharge evaluation, vaginal Gram stain and white cell count, and culture for yeast and Lactobacillus, including colony count and hydrogen peroxide production.

Results: Of the 40 subjects assigned to each arm, 33 (82.5%) subjects in the ring-first arm and 31 (77.5%) subjects in the pill-first arm completed all study visits (P =.58). Most subjects reported few genital symptoms with either method, but 63% of subjects reported vaginal wetness during ring use compared with 43% during pill use. During ring use larger numbers of Lactobacillus colonies present were positive for hydrogen peroxide production (fold difference 2.67, 95% confidence interval 1.49, 4.78, P <.001). All other laboratory data, including yeast colony counts, Nugent Gram stain score, vaginal white blood cell count, vaginal pH, and discharge weight, were not significantly different by method.

Conclusion: Some women may notice an increase in vaginal wetness during contraceptive ring use yet the method is well tolerated and appears to improve the vaginal flora.

Publication types

  • Clinical Trial
  • Comparative Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Contraceptive Devices, Female / adverse effects*
  • Contraceptives, Oral*
  • Female
  • Humans
  • Vaginitis / epidemiology
  • Vaginitis / microbiology*


  • Contraceptives, Oral