A Study On The Progress Of Labor And Labor Outcomes Of Different Fetal Orientation At The Beginning Of The Active Stage Of Labor

Research Objectives:With the development of medicine today,dystocia is still inevitable.As well known,the persistent occipital posterior and persistent occipital transverse are the important reasons of dystocia and cesarean.In addition,persistent occipital posterior and persistent occipital transverse increase the incidence of lateral perineal incision,postpartum hemorrhage,perinatal fever,severe perineal laceration,and associated with neonatal asphyxia,neonatal complication.The study shows that the incidence of early delivery posterior occipital position is about 25%,the incidence of the second stage of labor posterior occipital position is about 15%,the incidence of persistent posterior occipital position is about 5%-12%;The incidence of early delivery transverse occipital position is about 19%-49%,the incidence of the second stage of labor transverse occipital position is about 10%-20%,and the incidence of persistent transverse occipital position is about 3%-8%.The first stage of labor active period for the uterine mouth expansion and fetal head down acceleration stage,is an important stage of labor progress,this study collected maternal clinical data,explore the first stage of labor active starting point of different orientation of labor characteristics and labor outcomes,explore after occipital posterior and occipital transverse weather affect the progress of labor,whether affect the delivery mode,whether increase the maternal and infant adverse outcomes.To explore whether it is helpful to clarify the fetal orientation at the beginning of the active period,and to provide new ideas for clinical labor management.Research methods:This study is a single-center retrospective cohort study,analyzed clinical data of women delivered at Dalian Municipal Women and Chlidren’s Medical Center(Group)from January 2020 to December 2021,met the inclusion criteria and not met the exclusion criteria.A total of 571 women were included.According to the different fetal orientation at the beginning of the active period,they were divided into three groups,anterior occipital position(OA)group,transverse occipital position(OT)group,and posterior occipital position(OP)group.The basic data,obstetric data,labor time,delivery mode and maternal and infant outcomes among the three groups were counted and analyzed and compared.Results:A total of 571 maternal cases were included,with 182 in OA group,290 in OT group and 99 in OP group.There were no significant differences in maternal age,height,weight,and BMI;Gestational weeks in OP(40.02 ± 0.84 weeks)was longer than OT(39.58 ± 1.02 weeks)and OA(39.73 ± 0.87 weeks),with significant difference(P<0.001),and no significant difference between OA and OT groups.The proportion of primimothers among the three groups(80.8% in OA group,83.1% in OT group,89.9%in OP group,P=0.138),the proportion of spontaneous labor women(62.6% in OA group,61.7% in OT group,51.5% in OP group,P=0.146),the proportion of women with complications(45.1% OA group,37.0% OT group,46.5% OP group,P=0.107)was not different;The proportion of oxytocin was higher in OP group(58.6%)than in OT group(45.5%)and OA group(41.8%),The proportion of labor analgesia was higher in OT group(71.7%),OP group(78.8%)than OA group(63.7%),the difference was statistically significant.Latency time of 300min(191,450)in the OA group,360min(240,499)in OT group,360min(240,480)in OP group,there was no significant difference in the incubation time of the three groups;Active period duration OT group,OP group leader in OA group,120min(60,180)for OA group the OT group for 150min(75,210),OP group 180min(120,240),The difference is statistically significant;The second labor duration in the OP group was significantly longer than the OA and OT groups,50min(25,102)for OA group,The OT group for 52min(27,105),The OP group was used in 86min(47,136),the difference was statistically significant.The total stage of labor in OT group 630(592-668)min and OP group 675(649-701)min were longer than OA group 530(482-579)min,which were statistically significant.Among the 571 women,389 women had abnormal fetal orientation in early labor,and the proportion of active early fetal orientation was 68%;327 women were able to deliver to anterior occipital position by natural rotation or freehand rotation,with rotation was 84%;62 cases were unable to rotate to anterior occipital position,and the proportion of rotation failure was 16%.The vaginal delivery rate OA group was higher than OT group and OP group,(93.4% in OA group,87.9% in OT group,72.7% in OP group,P <0.001),and the transit cesarean section rate in OT group and OP group was higher than OA group,(6.6%,12.1% in OT group,2.1% in OT group,27.3% in OP group,P <0.001).Neonatal birth weight OP(3580.30±377.27g)was greater than OA(3460.05±382.11g)and OT(3462.81±374.12g),statistically significant(P=0.018),but not different in postpartum bleeding rate,postpartum urinary retention rate,neonatal Apgar score,NICU admission,neonatal complications,and umbilical artery blood gas analysis.Research Conclusion:1.At the beginning of the active period,the vaginal delivery duration varies in different fetal positions,the transverse occipital position and posterior occipital labor period is prolonged,and the active period,second labor period and total labor duration is longer than the anterior occipital group.In addition to fetal orientation,primipara,labor analgesia and weak contractions can also lead to prolonged labor time.2.Abnormal fetal orientation at the beginning of the active period reduces the rate of vaginal delivery,and the increases the rate of transit cesarean section.In addition,primipara,newborn weight and weak contractions can also affect delivery patterns.3.At the beginning of the transverse occipital position or posterior occipital position in the active stage of the first stage of labor,they are mostly transferred to the anterior occipital position before delivery,and most of them are successfully rotated in the second stage of labor.Abnormal fetal orientation during the active period increases the need for oxytocin and labor analgesia,but it does not increase the occurrence of poor maternal and infant prognosis.4.Defining the fetal orientation in the early active period is helpful for labor process management.