In 2009, researchers from Seoul University published the results of a clinical study they conducted to explore whether or not dry vaginal steaming with mugwort decreases menstrual cramps. The study included a total of 40 participants who completed pre-treatment and post-treatment questionnaires and urine tests. Seven days before their expected period, 20 of the 40 participants completed four consecutive days of vaginal smoking with mugwort. Afterwards, their results were compared with the other half of the group that did not do any dry steaming.

The researchers found that the group that completed dry vaginal steaming experienced significantly less menstrual cramps than the control group. The paper concludes that “dry vaginal steaming is an effective treatment for decreasing menstrual cramps”. Because of its convenience and accessibility, the authors propose that vaginal steaming should be standard nursing practice and education.