[Characteristics of uterine contraction and stages of labor under continuous epidural block anesthesia].

Objective: To observe the characteristics of uterine contraction and stages of labor during delivery under continuous epidural block anesthesia.

Methods: Totaling 213 parturients in spontaneous labor under epidural block anesthesia with dilated cervical orifice of 3 cm were monitored for the contraction cycle, duration, intensity and curve types of uterine contraction, and recordings were made for 30 min before and 30, 60 and 120 min after the anesthesia took effect, respectively. The duration of the active phase in the first, second and third stages of labor was compared between 421 cases with anesthesia and 237 without anesthesia.

Results: Significant difference was noted in the objective indexes of uterine contraction recorded after anesthesia had taken effect (P<0.05) in comparison with those before anesthesia, suggesting significantly attenuated uterine contraction after anesthesia, whereas these indexes underwent no significant further variation as compared between different time points after anesthesia (P>0.05). The average active phase in the first stage was significantly shorter in anesthesia group than that in the control group (P<0.05), but the average duration of the second and third stages of labor differed little between the two groups with appropriate use of oxytocin under strict monitoring (P>0.05). The rates of obstetric forceps utilization and use of oxytocin were higher in anesthesia group than in the control group (P<0.05).

Conclusion: Epidural block anesthesia produces certain influences on uterine contraction and stages of labor during delivery, for which appropriate treatment measures may prove beneficial.