Painful periods (dysmenorrhea), characterized by cramping lower abdominal pain that may radiate to the lower back and upper thighs, are extremely common. From 20% to 90% of adolescents in a US study have reported such symptoms with 15% describing them as severe. A UK study found that the prevalence of dysmenorrhea was between 45% to 97%. Researchers from the Department of Obstetrics and Gynecology at the University of Auckland in New Zealand conducted a systematic review to assess the evidence for the effectiveness of exercise in the treatment of symptoms associated with dysmenorrhea. Systematic reviews look exhaustively for all available studies in the worldwide medical literature and then rate them according to the quality of the studies and the extent to which the results provide strong evidence for a recommendation. Note that the review did not try to explain any benefit (e.g., endorphin release as an analgesic) but just to establish if exercise helped in relief of menstrual pain.

The criteria for studies to be included in the review were quite strict (pain affecting daily activity; pain lasting at least one day; pain in the majority of menstrual cycles; no irregular or infrequent cycles; no intra-uterine contraceptive devices or oral contraceptive pills). Given the widespread scope of the problem, it is astonishing that the authors were only able to find four potential trials to review. Even more surprising is that they had to reject three of these trials because of poor scientific approaches used in these studies.

The remaining trial was conducted almost 25 years ago and examined the effect of aerobic training on relief of period pain. Even though there were some serious questions about methodology and some questionable gaps in the report, there was a suggestion that exercise was effective in relieving pain.

The authors of the review concluded: “Although there is some evidence from non-randomized studies to support the use of exercise in alleviating the symptoms associated with dysmenorrhea, available evidence is severely limited in volume and quality. Further research is required in this area before any definitive conclusions can be made."

This seems like yet another example where research on a health issue of critical importance for women has been neglected. Perhaps it is time for those of you in the US to lobby your elected representatives in Washington encouraging them to give a directive to the National Institutes of Health to study exercise as a potential solution to a significant problem faced by many women. There is an answer to this question – someone just needs to study it in the appropriate way!

Read the abstract of the systematic review here.