Researchers in China have shown that the acupuncture point sanyinjiao (SP-6), traditionally used for a variety of gynaecological problems, does indeed have a specific and immediately beneficial effect on period pain.
Fifty-two women with period pain were each assigned to one of four groups: electroacupuncture at SP-6; electroacupuncture at a corresponding acupuncture point on the opposite side of the leg; elecroacupuncture at an adjacent non-acupuncture point; no acupuncture. They received 10 minutes treatment at a time when they scored their pain as 4/10 or greater, and a further 30 minutes treatment on the following two days. The SP-6 treatment group experienced highly significant reductions in pain scores, compared to the other groups.
(A Comparative Study on the Immediate Effects of Electroacupuncture at Sanyinjiao (SP-6), Xuanzhong (GB-39) and a Non-Meridian Point, on Menstrual Pain and Uterine Arterial Blood Flow, in Primary Dysmenorrhoea Patients. Pain Med, Oct 2010.)