Randomised trial, 1991
Does taking a placebo pill reduce PMS symptoms?
This study found that placebo significantly reduced PMS symptoms during 3 months of treatment. However, individual women responded very differently, and without an active comparison group it's unclear if improvement was due to the placebo effect or other factors.
What they did
29 women with PMS kept daily symptom records for 6 menstrual cycles (3 as control, 3 taking placebo). Weekly urine samples tested for pregnanediol (a hormone marker). Researchers analyzed patterns of psychological and physical symptoms during both control and placebo phases.
What they found
Placebo significantly improved premenstrual symptoms overall, with improvements lasting throughout the 3-month treatment period. However, individual women showed marked differences in how much they responded to placebo, ranging from good to poor response. One unexpected finding: psychological symptoms shifted to begin closer to menstruation (within a few hours of onset) rather than in earlier phases of the cycle.
What it means for you
Placebo can reduce PMS symptoms, and the effect lasted 3 months in this study. However, women responded very differently, suggesting placebo works better for some women than others. The study didn't compare placebo to an active treatment, so it's unclear whether improvements were due to the placebo effect specifically or other factors like attention and time.
29
women in study
6 cycles
cycles tracked per woman
3 months
treatment duration
About the study
- Original title
- Mood and physical symptom cyclicity in women with the premenstrual syndrome: Unexpected response to placebo treatment
- Authors
- Mary G. Metcalf, James Livesey, J. Elisabeth Wells
- Journal
- Journal of Psychosomatic Obstetrics & Gynecology
- Year
- 1991
- Study design
- Randomised trial
- Participants
- 29
- What was tested
- Placebo pills for 3 menstrual cycles, following 3 control cycles
- Read the paper
- doi.org/10.3109/01674829109078008
Topics
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