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.