Dysmenorrhoea is painful cramps originating in the uterus just prior to or during menstruation. It can be primary (i.e. without any organic pathology) or secondary (i.e. associated with a pathological condition, such as endometriosis or ovarian cysts). The pain usually lasts between 8 and 72 hours.(Fraser 1992)
Adolescent girls are more likely than older women to have primary dysmenorrhoea because the condition can get better with age. Secondary dysmenorrhoea tends to be less common in adolescents, as onset of causative conditions may not have occurred yet. Estimates suggest that around 25-50% of adult women and about 75% of adolescents experience pain with menstruation, and some 5-20% report severe pain that prevents them from carrying on with their usual activities.(Zondervan 1998; Harlow 2004) The longer the mean duration of menstruation the more severe the dysmenorrhoea. Also, younger age at menarche and cigarette smoking have been associated with dysmenorrhoea.(Harlow 1996; Sundell 1990)
Conventional treatment is aimed at relieving pain and includes NSAIDs, the oral contraceptive pill, depo-medroxyprogesterone acetate, levonorgestrel-releasing intrauterine device, danazol and leuprolide acetate.
Fraser I. Prostaglandins, prostaglandin inhibitors and their roles in gynaecological disorders. Bailliere's Clinical Obstet Gynaecol 1992;6:829-57.
Harlow SD, Campbell OM. Epidemiology of menstrual disorders in developing countries: a systematic review. BJOG 2004;111:6-16.
Harlow SD, Park M. A longitudinal study of risk factors for the occurrence, duration and severity of menstrual cramps in a cohort of college women. Br J Obstet Gynaecol 1996;103:1134-42.
Sundell G et al. Factors influencing the prevalence and severity of dysmenorrhoea in young women. Br J Obstet Gynaecol 1990;97:588-94.
Zondervan KT et al. The prevalence of chronic pelvic pain in the United Kingdom: a systematic review. Br J Obstet Gynaecol 1998;105:93-9.
How acupuncture can help
Recent systematic reviews of randomised controlled trials (RCTs) found that both acupuncture (Cho 2010a) and acupressure (Cho 2010b) are effective for primary dysmenorrhoea, providing significantly more pain relief than pharmacological treatments. Comparisons of acupuncture with sham acupuncture produced variable results and no significant difference overall (Cho 2010a). This is consistent with the viewpoint that sham controls are active interventions, not placebos, providing unreliable results with a tendency to underestimate acupuncture's effects (Lundeburg 2009; Sherman 2009). Two earlier systematic reviews (Yang 2008; Proctor 2002) found a lack of high quality trials on acupuncture for dysmenorrhoea and so could not draw firm conclusions. Since then there have been further RCTs, especially from China (Wong 2010; Chen 2010; Zhu 2010; Wang 2009), hence the stronger conclusions in the 2010 reviews. The most compelling evidence comes from a large, high quality German trial that also found acupuncture to be cost-effective (Witt 2008). Also see our other factsheets on Premenstrual syndrome and Endometriosis. For other gynaecological conditions the research base is scanty (Smith 2010). For example, a systematic review of trials on acupuncture for fibroids found no trials that fit their inclusion criteria (Zhang 2010). (see Table overleaf)
Acupuncture may help reduce symptoms of dysmenorrhoea by:
- regulating neuroendocrine activities and the related receptor expression of the hypothalamus-pituitary-ovary axis (Liu 2009; Yang 2008)
- increasing nitric oxide levels, which relaxes smooth muscle and hence may inhibit uterine contractions (Wang 2009)
- increasing relaxation and reducing tension (Samuels 2008). Acupuncture can alter the brain's mood chemistry, reducing serotonin levels (Zhou 2008) and increasing endorphins (Han, 2004) and neuropeptide Y levels (Lee 2009), which can help to combat negative affective states
- stimulating nerves located in muscles and other tissues, which leads to release of endorphins and other neurohumoral factors, and changes the processing of pain in the brain and spinal cord (Pomeranz, 1987; Zijlstra 2003; Cheng 2009);
- reducing inflammation, by promoting release of vascular and immunomodulatory factors
- (Zijlstra 2003; Kavoussi 2007)