Ziba Raisi Dehkordi - Department of Midwifery, School of Nursing and Midwifery, Shahrekord University of Medical Sciences, Shahrekord, Iran
Elham Adibmoghaddam - Ph.D student of Reproductive Health, Student research committee, Nursing and midwifery school, Isfahan University of Medical Sciences, Isfahan, Iran
Hadis Sourinejad - Ph.D student of Reproductive Health, Student research committee, Nursing and midwifery school, Isfahan University of Medical Sciences, Isfahan, Iran

The purpose of this study was to explore the effect of willow bark on the amount of menstrual bleeding in female students with primary dysmenorrhea DESIGN:This study is an experimental clinical trial. The subjects were 96 female students residing in dormitory at Shahrekord University of Medical Sciences in 2013. The inclusion criteria were as: being single, suffering from primary dysmenorrhea, having no genital organs disorder, having no systemic disease, having regular menstrual cycles, using no contraceptives, etc. The follow-up time was 6 menstrual cycles. The subjects were randomized into two groups: experimental (n=48) who willow bark capsule, and placebo (n=48 was prescribed a daily dose of extract containing 240 mg of salicin (group willow bark). The amount of menstrual bleeding was measured by Bleeding volume was determined by Higam table. Ordinal logistic regression and generalized estimating equation (GEE) were used to analyze the data. RESULTS: The amount of menstrual bleeding in the willow bark group was reduced in comparison to the placebo group the difference was statistically significant (p=0.025). No significant difference was observed for blood clot among the students (p=0.766). This study showed that willow bark was effective in reduction of menstrual blood loss .suggesting that it could be applied by midwives in a safe manner because of no side effects, simplicity and cost-effectiveness for all patients