Objective: To evaluate the effect of combined application of HANS(Han's Acupoint Nerve Stimulator) and diazepam and tramadol on labor pain and its influence on mother

fetus and newborn baby in order to find a safe

convenient and effective method for pain relief during labor.Methods: 270 normal term pregnancy and primipara with single vertex presentation were randomly divided into six groups: HANS+diazepam(diazepam 10 mg

iv)

HANS

diazepam(diazepam 10 mg

iv)

HANS+tramadol(tramadol 100 mg

im)

tramadol(tramadol 100 mg

im) and control group. All the methods for relieving pain were given when the cervixs were dilated to about 2～3 cm in diameter. The plate like electrodes of HANS were placed at Jiaji(EX B 2) and Ciliao(BL 32) for stimulating these points with frequency of 2/100 Hz alternately and intensity of 14～30 mA. Labor pain was evaluated by VAS(visual analogue scaling) and graded into four degrees at the time of one hour before and after analgesia

the cervix dilation being about 7～8 cm in diameter

second stage

and post labor respectively. Indexes of VAS

duration of labor

fetal cardiotocography

post partum bleeding

blood gas analysis of umbilical artery

Apgar score and asphyxia of different groups were compared.Results: ① The analgesic effective (markedly effective plus effective rate) rates of HANS+diazepam

HANS+tramadol and HANS were 90.3%

78.9% and 59.8% respectively. ② In the two groups of combination of HANS and medicines

the VAS at the time of one hour after analgesia

cervix dilation of 7～8 cm and second stage were significantly lower than those of pre analgesia (P<0.01). There were significant differences in VAS between each experimental group and control group in various stages. ③ In two medicine groups

the VAS at the time one hour after analgesia was much lower than that of pre analgesia (P<0.01)

but at the time of cervix dilating 7～8 cm and second stage

the VAS of diazepam group was the same to that of pre analgesia

and that of tramadol was higher than that of pre analgesia. ④ In HANS group

the VAS at the time one hour after analgesia and second stage were much lower than that of pre analgesia(P<0.01)

at the time of cervix dilating 7～8 cm

the VAS was lower than that of pre analgesia(P<0.05). ⑤ The VAS of HANS+diazepam at the time of one hour after analgesia and the second stage were much lower than those of the rest 5 groups. There was no statistical difference between tramadol and HANS+tramadol groups in VAS at the time of cervix dilating 7～ 8 cm

but VAS of tramadol and HANS+tramadol groups were much lower than those of the other three groups(P<0.01). ⑥ There were no significant differences among the six groups in duration of labor

delivery mode

post partum bleeding

fetal distress

neonatal asphyxia and umbilical blood PH.Conclusion: HANS combined with some sedative or analgetics (diazepam

tramadol) has good analgesic effect on labor pain. No side effect was found in mothers and babies. It is suggested that combination of HANS and diazepam or tramadol is safe

convenient and effective for relieving pain during labor.