Immediate Effect of Acupuncture at Sanyinjiao (SP6) and Xuanzhong (GB39) on Uterine Arterial Blood Flow in Primary Dysmenorrhea

Objective: The objective of this study was to compare immediate effect of acupuncture at SP6 on uterine arterial blood flow in primary dysmenorrhea with that of GB39. Design: This was a prospective, randomized clinical trial. Setting: Sixty-six (66) patients with primary dysmenorrhea from the Affiliated Hospital of Shangdong University of Traditional Chinese Medicine were recruited. Interventions: The SP6 group (n=32) was treated with manual acupuncture at bilateral SP6 for 5 minutes after obtaining needling sensation (de qi) during the period of menstrual pain, whereas the control group (n=34) was needled at GB39 of both sides for 5 minutes when they suffered menstrual pain. Main outcome measures: Differences in pulsatility index (PI), resistance index (RI), and ratio of systolic peak and diastolic peak (A/B) in uterine arteries were the main outcome measures. Results: Highly significant reductions were observed in the SP6 treatment group 5 minutes after treatment in menstrual pain scores (8.17 +/- 1.90 versus 11.20 +/- 2.66; p<0.001), values of PI (1.75 +/- 0.48 versus 2.32 +/- 0.70; p<0.001), RI (0.72 +/- 0.11 versus 0.78 +/- 0.07; p<0.001), and A/B (4.33 +/- 1.37 versus 5.23 +/- 1.67; p<0.001). Compared with the GB39 control group, patients in the SP6 treatment group showed significant reductions in 5 minutes after treatment in the changes of menstrual pain scores (3.03 +/- 2.36 versus 0.00 +/- 0.29; p<0.001), values of PI (0.57 +/- 0.42 versus -0.10 +/- 0.58; p<0.001), RI (0.06 +/- 0.08 versus -0.03 +/- 0.15; p<0.01), and A/B (0.90 +/- 0.87 versus 0.23 +/- 1.02; p<0.01). There were no significant changes in menstrual pain scores, values of PI, RI, or A/B before and after treatment in the GB39 control group (p>0.05). No adverse events from treatment were reported. Conclusions: This study suggests that needling at SP6 can immediately improve uterine arterial blood flow of patients with primary dysmenorrhea, while GB39 does not have these effects.