Objective To observe the influence of acupuncture needle stimulation-induced sharp pain on the curative effect of acupuncture therapy for primary dysmenorrhea(PD)patients with cold damp stagnation syndrome(CDSS).MethodsA total of 87 PD patients with CDSS experiencing abdominal pain(≥40mm in visual analogue scale

VAS)were randomly assigned to deqi-expectation group and no-deqi-expectation group which were further divided into deqi-expectation+sharp pain(n=31)

deqi-expectation+no-sharp pain(n=12)

no-deqi-expectation +sharp pain(n=17)

no-deqi-expectation +nosharp pain(n=27)groups.On the first day of abdominal pain attack

bilateral Sanyinjiao(SP 6)were punctured respectively with thicker needles with deeper insertion for deqi-expectation patients and thin filiform needles with shallow insertion for no-deqiexpectation patients.The needles were manipulated for 30 swith uniform reinforcing-reducing method for all the deqi-expectation patients

which was repeated once again every 10 min during 30 min of needle retention.The VAS was used to evaluate the patients' abdominal pain severity before treatment and 0

10 min after acupuncture needle withdrawal.Results Following acupuncture stimulation of SP 6

the VAS scores of menstrual pain at both 0min and 10 min after withdrawing acupuncture needles were significantly decreased in the deqi-expectation+ sharp pain group

deqi-expectation+ no-sharp pain group

no-deqi-expectation+sharp pain group and no-deqi-expectation + no-sharp pain group(P<0.05)

and that of 10 min post-needle withdrawal was markedly lower than that of 0min in the deqi-expectation+ sharp pain group(P<0.05).No significant differences were found in the VAS difference values at different time-points between deqi-expectation plus sharp pain and deqi-expectation+no-sharp pain groups

and between no-deqi-expectation+sharp pain and no-deqi-expectation+no-sharp pain groups(P>0.05).Conclusion Acupuncture stimulation of SP 6has an immediate analgesic effect in PD women with cold damp stagnation syndrome

which was not affected by needling-induced sharp pain

deqi-expectation

and thicker or thinner needle with shallow and deeper insertion.