An observational study was conducted to investigate the association of tongue features with menstrual pain during menstrual cycle. The study conducted at Kyung Hee University Medical Center included 48 eligible women between 20 to 29 years and divided into two groups namely Group A and B according to their visual analog scale (VAS) scores. A total number of 24 females suffering from primary dysmenorrhea (PD) caused by qi stagnation and blood stasis syndrome with VAS ≥ 4 were included in Group A whereas Group B included a total number of 24 females with lesser premenstrual symptoms and VAS < 4. During all the four menses-follicular-luteal-menses phases female participants of both the groups visited the research center, and their tongue images were recorded by computerised tongue image analysis system (CTIS).

The P value calculated (P = 0.031 PD group and P = 0.029 control group) as results revealed that the colour of tongue coating and tongue coating was different in PD group and significantly lower than the control group. The study concluded that tongue features obtained from the CTIS could be an additional method for the differentiation of syndromes and prognosis in PD.