Abstract: The objective was to study the efficiency of inhaling laughing gas for labor pains, delivery processes, delivery ways and its effects on mother and fetus. 100 primiparas were randomly divided into the observational group and the control group. The control group was given the same treatments as that in the observational group except inhaling laughing gas. The degrees of labor pains, delivery processes, delivery ways, apgar scores and quantity of intrapartum hemorrhage between the two groups were measured. The score of the labor pains in the observational group was significantly lower than that in the control one (P<0.01). The duration of active phase in the observational group was significantly shorter than that in the control one (P<0.05). The total delivery process in the observational group was shorter than that in the control one (P>0.05). Conclusions: Analgesic labor with inhaling laughing gas produces a efficient labor pain relief, a shorter duration of active phase and shows no side effects on both mother and fetus, which is effective, simple and easy to be accepted.

Key words: laughing gas, labor, analgesic