Clinical study on efficacy and safety of vaginal balloon dilatation and labor analgesia with inhalation of nitrous oxide in oxygen

Objective:To investigate the efficacy and safety of vaginal balloon dilatation and labor analgesia with inhalation of 50% nitrous oxide in oxygen.Methods:A total of 120 cases of term primiparous women in labor were divided into two groups: study group (n=60) used vaginal balloon dilatation to dilate the vaginal and same time 50% nitrous oxide in oxygen was inhalated during labor for relieving labor pain, control group (n=60) intermittent inhalation of oxygen was carried out during labor.Two groups were compared with following indices: duration of the labor, delivery mode, meconium stained of amniotic fluid, postpartum bleeding volume, neonatal Apgar score, and side effect of nitrous oxide.Results:The efficiency of relieving labor pain in study group was much better than that of control group (P0.05).The length of first stage, second stage and the length of labor when the vaginal balloon dilatation were used in active phase were shorter than those in control group (P0.05).Rate of cesarean section in study group was lower than that of control group (P0.05).There were no significant differences in meconium stained amniotic fluid, postpartum bleeding volume, and neonatal Apgar score between two groups (P0.05).Conclusion:The application of the vaginal balloon dilatation and inhalation of 50% nitrous oxide in oxygen is convenient and safe during labor. The measure is useful in relieving labor pain, accelerating labor course,lowering cesarean section rate without any side effect on mother and baby.