OBJECTIVES:: Dysmenorrhea is a prevalent problem and decreases the quality of life in women and adolescent girls. The aim of this study was to compare the effectiveness of herbal products and nonsteroidal anti-inflammatory drugs (NSAIDs) in the treatment of dysmenorrhea in women with non-obstructive genital tract congenital anomalies. METHODS::  This double-blind clinical trial was carried out in women with mild and moderate dysmenorrhea and non-obstructive reproductive tract congenital anomalies in Lviv Regional Reproductive Health Center. The women were randomly divided into two groups which received the extracts of vitex agnus castus and mefenamic acid. Dysmenorrhea severity was determined by Visual Analog Scale (VAS) for pain (Larroy C., 2002; Aksoy AN et al., 2014) during one cycle before and two cycles after the intervention. RESULTS:: There were no differences between two groups for demographic or descriptive variables. The mean age of the women was 2 yearshere was no significant difference in the mean of severity of dysmenorrhea during one cycle before the intervention between groups, but the difference was significant during two cycles after the intervention. Vitex agnus castus had similar effects as mefenamic acid on dysmenorrhea. Comparison of VAS showed that the participants in vitex agnus castus and mefenamic acid groups had significantly lower pain in the first and in the second months after start of the treatment (P < 0.05). Severity of pain before taking vitex agnus castus was 5.1±2.1, after treatment it was 2.9±1.7. In group women taking mefenamic acid severity of pain before treatment was 4.9±2.0, after treatment – 2.7±1.9. No side effects were reported in both groups. CONCLUSIONS:: Vitex agnus castus was as effective as mefenamic acid in decreasing the pain severity of dysmenorrhea in women with reproductive tract congenital anomalies.