Yoga for menstrual pain in primary dysmenorrhea: A meta-analysis of randomized controlled trials

To assess the overall effect size of the impact of yoga on menstrual pain in primary dysmenorrhea. Randomized controlled trials that were published in the English language until December 2018 in PubMed, EMBASE, Web of Science, and the Cochrane Library electronic databases were searched. The methodologies from 4 trials conducted on 230 participants with primary dysmenorrhea were included in this meta-analysis to compare the effects that performing a yoga program has on menstrual pain (n = 129) to the effects of not performing yoga (n = 101). The overall effect size of the impact of a yoga program on menstrual pain in primary dysmenorrhea was high with a standardized mean difference of −2.09 (−3.99 to −0.19) (p = 0.031) among the effect sizes of the 4 trials (95% confidence interval). Yoga is an effective intervention for alleviating menstrual pain in women with primary dysmenorrhea.