Chinese herbal medicine for primary dysmenorrhoea

Background Conventional treatment for primary dysmenorrhoea has a failure rate of 20% to 25% and may be contraindicated or not tolerated by some women. Chinese herbal medicine may be a suitable alternative. Objectives To determine the efficacy and safety of Chinese herbal medicine for primary dysmenorrhoea when compared with placebo, no treatment, and other treatment. Search strategy The Cochrane Menstrual Disorders and Subfertility Group Trials Register (to 2006), MEDLINE (1950 to January 2007), EMBASE (1980 to January 2007), CINAHL (1982 to January 2007), AMED (1985 to January 2007), CENTRAL (The Cochrane Library issue 4, 2006), China National Knowledge Infrastructure (CNKI, 1990 to January 2007), Traditional Chinese Medicine Database System (TCMDS, 1990 to December 2006), and the Chinese BioMedicine Database (CBM, 1990 to December 2006) were searched. Citation lists of included trials were also reviewed. Selection criteria Any randomised controlled trials involving Chinese herbal medicine versus placebo, no treatment, conventional therapy, heat compression, another type of Chinese herbal medicine, acupuncture or massage. Exclusion criteria were identifiable pelvic pathology and dysmenorrhoea resulting from the use of an intra-uterine contraceptive device. Data collection and analysis Quality assessment, data extraction and data translation were performed independently by two review authors. Attempts were made to contact study authors for additional information and data. Data were combined for meta-analysis using either Peto odds ratios or relative risk (RR) for dichotomous data or weighted mean difference for continuous data. A fixed-effect statistical model was used, where suitable. If data were not suitable for meta-analysis, any available data from the trial were extracted and presented as descriptive data. Main results Thirty-nine randomised controlled trials involving a total of 3475 women were included in the review. A number of the trials were of small sample size and poor methodological quality. Results for Chinese herbal medicine compared to placebo were unclear as data could not be combined (3 RCTs). Chinese herbal medicine resulted in significant improvements in pain relief (14 RCTs; RR 1.99, 95% CI 1.52 to 2.60), overall symptoms (6 RCTs; RR 2.17, 95% CI 1.73 to 2.73) and use of additional medication (2 RCTs; RR 1.58, 95% CI 1.30 to 1.93) when compared to use of pharmaceutical drugs. Self-designed Chinese herbal formulae resulted in significant improvements in pain relief (18 RCTs; RR 2.06, 95% CI 1.80 to 2.36), overall symptoms (14 RCTs; RR 1.99, 95% CI 1.65 to 2.40) and use of additional medication (5 RCTs; RR 1.58, 95% CI 1.34 to 1.87) after up to three months of follow-up when compared to commonly used Chinese herbal health products. Chinese herbal medicine also resulted in better pain relief than acupuncture (2 RCTs; RR 1.75, 95% CI 1.09 to 2.82) and heat compression (1 RCT; RR 2.08, 95% CI 2.06 to 499.18). Authors' conclusions The review found promising evidence supporting the use of Chinese herbal medicine for primary dysmenorrhoea; however, results are limited by the poor methodological quality of the included trials.