Vaginal pH effects caused by OCs and various copper and inert IUDs

Contracept Deliv Syst. 1983 Jul;4(3):187-93.


PIP: The effects of oral contraceptives (OCs) and various copper and inert IUDs on human vaginal pH were evaluated. A thorough history and examination were performed on the 331 women selected for the study. Participants were divided into 3 groups: 110 control cases of normally menstruating women (34 at early follicular, 44, at late follicular, 22 at early luteal phases); 83 women using combined oral contraceptives (COCs, 41 women were Primovlar users and 42 women were using Anovlar 1, 23 at early follicular, 18 at late follicular, 22 at early luteal phase and 20 at late luteal phase); and 138 IUD users (71 Lippes loop and 57 copper IUD users, i.e., Cu T, Cu7, and ML Cu250). With the patient in the lithotomy position, the labia majoras were widely separated. The electrode of the pH meter gently touched the lower portion of the vagina for determination of pH at this level. The speculum was opened, locked in situ, and the electrode determined the pH of the middle third of the vagina. The speculum was further introduced and the electrode touched the anterior and posterior fornices for their pH determination. Comparisons were made of the pH of middle third of the vagina of women using Anovlar 1, women using Primovlar, and the control cases. In Anovlar 1 users, there was a statistically significant drop in the mean vaginal pH at the early follicular phase. In other phases, the mean pH was increased significantly except in the early luteal phase. In Primovlar users a drop in the mean pH value during the early luteal phase was found. An increase in the mean vaginal pH was found in the remaining phases. The increase was statistically significant only in late luteal and follicular phases. In copper IUD users an increase of the mean vaginal pH at all phases of the menstrual cycle was found. This increase was significant in all phases except early luteal phase. In Lippes loop users, a significant increase in the vagina pH at all phases was found as compared to control cases, but this increase was insignificant in the early follicular phase. A larger increase was found in Lippes loop users as compared to Cu IUD users.

Publication types

  • Comparative Study

MeSH terms

  • Contraception*
  • Contraceptive Agents
  • Contraceptive Agents, Female*
  • Contraceptives, Oral*
  • Contraceptives, Oral, Combined*
  • Family Planning Services
  • Intrauterine Devices*
  • Intrauterine Devices, Copper*
  • Menstrual Cycle*
  • Menstruation*
  • Reproduction
  • Research


  • Contraceptive Agents
  • Contraceptive Agents, Female
  • Contraceptives, Oral
  • Contraceptives, Oral, Combined