A randomized, double-blinded, placebo-controlled pilot study to investigate the effectiveness of a static magnet to relieve dysmenorrhea

Objectives: The aim of this study was to investigate the hypothesis that a specially designed, static magnet of 2700 gauss, attached over the pelvic area, could relieve menstrual pain. Design: This was a randomized, double-blind, placebo-controlled, postal questionnaire study. Setting: The study was conducted in a primary care, single center. Participants: Sixty-five (65) women (mean age 29.1 +/- 1.52 years) were recruited from an advertisement in a London newspaper. The entry criterion was regular dysmenorrhea. The exclusion criterion was known secondary dysmenorrhea. Of the 65 women who were enrolled, 35 completed the study. Interventions: A questionnaire-based assessment was completed by each subject and checked by telephone before and after random allocation to use of either the static magnet device (2700 gauss) or an identical, weaker magnetic placebo device (140 gauss). Assessment was made by telephone before and after a complete menstrual cycle. None of the participants was examined or seen face-to-face. Main outcome measures: The main outcome measures were level of pain, using the McGill Pain and Visual Analogue Scales, and ratings of associated symptoms such as irritability, restriction of usual activities, and painkiller consumption. Results: There was a significant reduction (p < 0.02) in pain in the magnet group compared to the placebo group. Pain score differences (McGill pain score before - pain score after use of device) were - 17 (-53, 13) (median and interquartile ranges) in the magnet group and -5.0 (-29, 27) in the placebo group. The 95% Mann-Whitney confidence intervals for the median difference between the magnet and placebo groups (magnet - placebo) were -53.0 to 23.38. A reduction in irritability symptoms in the magnet group approached statistical significance (p = 0.056). Conclusions: Despite the small number of participants, the level of significance reached in the reduction of pain merits reporting. This is a pilot study to a much larger study of the same device as an analgesic in women with primary dysmenorrhea.