ObjectiveTo study the effects of the labor duration of the second stage on maternal and infant outcomes of single full-term first-born primipara in the new standard of labor.

MethodsThe clinical data of 269 cases of single full-term primipara with first appearance were retrospectively analyzed.The cases were divided into the control group(n=113, duration of the second stage of labor < 2 h) and observation group(n=156, duration of the second stage of labor>2 h) according to the length of the second stage of labor.The observation group subdivided into the group A(72 cases, duration of the second stage of labor for 2-2.5 h), group B(44 cases, duration of the second stage of labor for 2.5-3 h) and group C(40 cases, duration of the second stage of labor for 3 h) according to the duration of the second stage of labor, and the mode of delivery, pregnancy outcome and neonatal outcome were analyzed.

ResultsThe differences of the perineal lateral resection rate, maternal adverse outcomes and neonatal adverse outcomes between the observation group and control group were not statistically significant(P>0.05), and the maternal forceps assisted delivery rate and cesarean section rate in observation group were significantly higher than those in control group(P < 0.01).There was no statistical significances in the maternal delivery mode, maternal adverse outcomes and neonatal adverse outcomes between group A and control group(P>0.05).The episiotomy and forceps-assisted delivery rates, and incidence rates of postpartum fever, postpartum hemorrhage, puerperal infection and urinary retention in group B and group C were higher than those in control group and group A(P < 0.05), and the cesarean section rates in group B and group C were higher than that in control group(P < 0.05).The incidence rates of the neonatal asphyxia, macrosomia, shoulder dystocia and neonatal acidemia in group C were higher than those in control group and group A(P < 0.05).The incidence rate of shoulder dystocia in group B was higher than that in group A(P < 0.05), and the neonatal acidemia rate in group B was lower than that in group C(P < 0.05).

ConclusionsCompared with the duration of the second stage of labor under the traditional standard of labor, the prolongation of the second stage of labor under the new standard of labor has adverse effects on the maternal and infant outcomes.In order to reduce the rate of cesarean section and occurrence of adverse outcomes, it is necessary to closely monitor maternal vital signs.