Labor Pattern Of Nulliparous Women With Normal Neonatal Outcomes

ObjectiveStudy on the birth curve and the time limit of the nulliparous women with singleton,vertex,term gestation and normal neonatal outcomes.MethodsThis study is a prospective study.Between January 1,2015 and December 31,2015,3062 nulliparous women with a singleton term gestation,vertex presentation were deliver in Nanjing Drum Tower hospital.After exclusion of cesarean delivery,foreigners,adverse perinatal outcome in severe cases,1070 spontaneous and 726 induced labor were included in this work.Gathering general information,pregnant women in labor increased oxytocin and whether to use labor analgesia,birth weight,postpartum blood loss,labor time,cervical dilation sizes and time.Calculate the first labor,active and second duration of labor.A repeated-measures model was set up to analysis labor curves,while an interval-censored regression was to estimate the duration of labor centimeter by centimeter.Results1.Among 1070 nulliparous women,12.1%had epidural analgesia,and the average birth weight was 3365±384g,with 5.2%macrosomia.The median duration of the first stage of labor was 7.0 hours,the 95th percentiles was 15.5 hours.The median length of active period(95 percentile)was 1.2(4.0)hours,and the median(95 percentile)of the second labor period was 0.8(2.1)hours.The average labor curve indicated that the production process was slow before 4cm,and the production process was rapidly progressing after 4cm,and no significant deceleration period was observed.2.As for none premature rupture of membranes puerpera,the median(95 percentile)of the spontaneous labor was significantly lower than that of the induced labor(47(126)vs.50(156)min(P=0.007).However,there was no statistically significant difference between the two groups in the first production duration of 440(930)vs.465(1028)min.The average labor curve indicated that the spontaneous labor was similar to that of the first stage of labor.3.Among premature rupture of membranes puerpera,the median length of first labor of spontaneous labor(95 percentile)was 330(921)vs.395(1064)min(P=0.000),which was significantly shorter than the induced labor(P= 0.030).but there was no statistical difference between the two groups(P=0.147)in the second labor time 48(153)vs.53(174)min.ConclusionIn this study,before cervical dilation 5 cm,spontaneous labor may need four hours to cervical dilation 1 cm;between 5-6 cm,need 3 hours;6 cm or more,the progress of each 1 cm may still need to 2 hours or more.As for none premature rupture of membranes puerpera,there was no significant difference between the spontaneous labor and the induced labor in the length of first labor.Among premature rupture of membranes puerpera,the first stage of spontaneous labor was shorter than in the induced labor.