Adult females appear to have considerable knowledge gaps regarding the efficacy of contraceptives – most over-estimate the effectiveness of condoms, the ring, the patch, the pill, and depo-medroxyprogesterone acetate, researchers from Washington University in St. Louis reported in the American Journal of Obstetrics and Gynecology.

Dr. David L. Eisenberg and team set out to find out how much women really know about the effectiveness of various contraceptives.

They carried out a cross-sectional analysis of a questionnaire which had been filled in by 4,144 female participants – they had all been enrolled in the Contraceptive CHOICE Project. Although the women in the Project received contraceptive counseling and eventually chose their own method of birth control – the questionnaires were filled before counseling took place.

The questions were simple, and asked them, for each contraceptive device or method:

    “What percentage would become pregnant in a year?”.

    They could choose from the following options:

    <1%, 1-5%, 6-10%, >10%, don’t know.”

The researchers found that:

  • 86% of them knew that the risk of becoming pregnant in one year without any method of the contraception was more than 10%

  • Over 45% overestimated the efficacy of
    – depo-medroxyprogesterone acetate
    – pills
    – the patch
    – the ring
    – condoms

  • Those who chose intrauterine devices were considerably more accurate in estimating their efficacy, compared to those who opted for the ring, the patch, or the pill

In an Abstract in the same journal, the authors wrote:

“This cohort demonstrated significant knowledge gaps regarding contraceptive effectiveness and over-estimated the effectiveness of pills, the patch, the ring, depo-medroxyprogesterone acetate, and condoms.”

Written by Christian Nordqvist