Maternal And Neonatal Short-term Outcomes Associated With Cesarean Delivery For Social Factors:a Retrospective Cohort Study

Cesarean delivery for social factors, also known as cesarean delivery on maternal request (CDMR), is defined by the American College of Obstetricians and Gynecologists (ACOG) as a cesarean delivery for a singleton pregnancy on maternal request at term in the absence of any medical or obstetric indications. In recent years, by the promotion of Chinese Family Planning Policy and the development of analgesic techniques, an increasing number of normal nulliparous chose to undergo a cesarean delivery for social factors as their method to give birth. Currently, cesarean delivery for social factors has drawn heightened interest and publicity. How the cesarean delivery for social factors will impact the maternal and neonatal prognosis? This issue has become the one of hottest issue on international concern.On maternal and neonatal prognosis delivered by cesarean section or natural delivery, there were a large number of clinical studies found that all perinatal maternal and neonatal complications incidence rates associated with cesarean section were higher than natural childbirth, and it had become the generally accepted view among the clinicians. However, most women who delivered by cesarean section were in a high-risk status, the adverse outcomes were difficult to distinguish from due to the complications occurred during the pregnancy to due to the cesarean section itself. Most studies on maternal and neonatal outcomes associated with cesarean delivery on maternal request abroad selected the cases of breech pregnancy as their study object, but breech pregnancy was a non-normal pregnancy status itself, so the application of the conclusions of those studies had their unique and significant limitations. And now, there is no study uses the cases of completely normal nulliparous.We conducted a retrospective cohort study, selected the cases of completely normal pregnancy nulliparous, in order to exclude the influence of confounding factors as much as possible, to analyze the impact of different mode of delivery on maternal and neonatal short-term outcomes.Chapter1The Influence of Cesarean Delivery for Social Factors on Cesarean Section Rate[Objectives] The aim of this study is to analyze the influence of cesarean delivery for social factors on cesarean section rate, to provide basis for developing specific measures to reduce the rate of cesarean section.[Methods]1Data collectionWe conducted a retrospective study which included a total of3040cases delivered by cesarean section in Nanfang hospital between January2005and December2009.2Classification of cesarean section indicationsAccording to the second version of Chinese Obstetrics and Gynecology, the second version of Obstetrics and Gynecology Surgery and the seventh version of Obstetrics and Gynecology, the indications for cesarean section were divided into the following categories:cephalopelvic disproportion, fetal distress, abnormal fetal position, delivery process abnormalities, pregnancy combined with other disease, pregnancy complications, abnormal pelvis, social factors, previous history of cesarean section, and others.3MethodCalculate the cesarean section rate, vaginal delivery rate, and assisted vaginal delivery rate for every year, to learn the trend of different mode of delivery; via collect and analyze the cases of cesarean section, to learn the changes in the composition of cesarean section indications and the main factors affecting the rate of cesarean section in this5years; analyze the trend of the constituent ratio of cesarean delivery for social factors and repeated cesarean section, to learn their impact on cesarean section rate; analyze the constitution of the indications of previous cesarean section in women who asked for a repeat cesarean section just due to the scar of the uterus, to learn the main cause for a repeat cesarean section.4Statistical analysisUse statistical software SPSS13.0for statistical analysis and graphing. Frequency data described by percentage (%), the trend of rates or constituent ratios used the Spearman rank correlation test. P<0.05indicated the difference was statistical significant.[Results]1Vaginal delivery rate increased over the years (Spearman rank correlation coefficient0.900, P=0.037), the vaginal delivery rate was49.56%in2005, by2009, it increased to63.33%. Cesarean section rate decreased over the years (Spearman rank correlation coefficient-0.900, P=0.037), it decreased from50.31%in2005to35.89%in2009. The average cesarean section rate was high, it was42.30%. The rate of assisted vaginal delivery was0.78%in this five-year period.2In this five-year period, the change in the rank of main cesarean section indications was not significant. Always in the top three were social factors, pregnancy complications, and previous history of cesarean section. Each year, cesarean sections caused by these three indications were more than half of total cesarean sections.3There was no significant correlation between the constituent ratios of cesarean delivery for social factors and the year, it increased from2005to2007, but decreased from2007to2009. Repeated cesarean section constituent ratios increased over the years (Spearman rank correlation coefficient1.000, P<0.01), it was14.64%in2005, by2009, it rose to18.97%.4There were more than1/3(36.65%) pregnant women, who asked for a repeat cesarean section just due to the scar of the uterus, were indicated by social factors at their previous cesarean section.[Conclusion]Although the cesarean section rate had a declining trend, but the average cesarean section rate was still high. Cesarean delivery for social factors and having a previous history of cesarean section asking for repeated cesarean section were the main causes for the high average cesarean section rate. The increase of cesarean delivery for social factors will lead to increasing risk of subsequent pregnancy, make the chance for repeat cesarean section increased, and thus contributed to the high average rate of cesarean section. Therefore, cesarean delivery for social factors is the most fundamental reason for high average cesarean section rate.Chapter2Maternal and Neonatal Short-term Outcomes Associated with Cesarean Delivery for Social Factors:A Retrospective Cohort Study[Objective] Exclude the influence of confounding factors as much as possible, to analyze maternal and neonatal short-term outcomes associated with cesarean delivery for social factors, providing the appropriate reference on mode of delivery selection for normal nulliparous.[Methods]1Data collectionWe conducted a retrospective cohort study. According to the inclusion and exclusion criteria, a total of1172nulliparous with a cephalic term singleton pregnancy and without cesarean section indications, who delivered in our hospital between January2005and December2009, were selected.336of which were cesarean delivery for social factors (CD group), others were spontaneous vaginal delivery. In accordance with the ratio of1:2, we randomly selected672nulliparous from the spontaneous vaginal delivery women as the control group (VD group).2Inclusion criteriaNulliparous、singleton pregnancy、term (38≤weeks gestational age<42weeks)、 cephalic presentation. 3Exclusion criteriaParous、twin or multiple pregnancies、gestational age<38weeks or>42weeks> assisted vaginal delivery with clear indications for cesarean section after IVF-ETn application of drug induced labor and so on.4Disease diagnostic criteriaMaternal postpartum diseases diagnostic criteria were in accordance with the seventh version of Obstetrics and Gynecology which Le Jie to edit in chief. Neonatal diseases diagnostic criteria were in accordance with the sixth version of Pediatrics which Yang Xiqiang and Yi Zhuwen to edit in chief and Zhu Futang Practical Pediatrics which Hu Yamei and Jiang Zaifang to edit in chief.5MethodCompare the differences of clinical characteristics of the nulliparous between the two groups. Analyze the risks of maternal and neonatal postpartum morbidities in CD group compared with VD group, and explore whether cesarean delivery for social factors is a risk factor for maternal and neonatal outcomes after controlling the potential confounding factors. Investigate the influence of maternal age and BMI on selection of different mode of delivery.6Statistical analysesUse statistical software SPSS13.0for statistical analysis. Measurement data description can be expressed by (mean±standard deviation), test the homogeneity of variance between the two groups, the homogeneity of variance applied a two sample t-test, heterogeneity of variance applied a t’ test; frequency data description based on percentage (%), applied Pearson χ2test or Fisher’s exact test, P<0.05indicated significant difference. Calculate the relative risk (RR) values and their95%confidence interval (95%CI) for maternal and neonatal outcomes. Logistic regression was used to adjust the fluencies of confounding factors between the two groups. Logistic regression analysis also was used to find the effect of maternal age and BMI on selection of mode of delivery.[Results]1The mean of maternal age (28.67±3.14vs26.38±3.40, t=10.315, P=0.000), BMI (26.45±2.12vs25.12±2.32, t=8.847, P=0.000), gestational age (39.76±0.78vs39.62±0.87, t’=2.542, P=0.011) were significantly higher in the CD group.2CD group was less likely to have the complication of postpartum hemorrhage (4.5%vs10.9%) compared with VD group, the difference was statistically significant (χ2=11.511, P=0.001), the RR was0.411(95%CI:0.239-0.705), the mean of the difference of prenatal and postnatal Hb is lower in the CD group (6.32+8.55vs15.31+10.20, t=13.895, P=0.000), between the two groups, there were no postpartum serious maternal complications and adverse outcomes due to the postpartum hemorrhage, such as DIC, uterine artery embolization, hysterectomy and maternal death. There was no difference in puerperal morbidity (0.9%vs0.4%) or breastfeeding rate (86.9%vs87.2%) between the two groups (P values were0.406and0.894, separately). After controlling for potential confounders, the adjusted OR of postpartum hemorrhage in the CD group was0.334(95%CI:0.183-0.612), the difference was statistically significant, while the other outcomes were not statistically significant.3The risk of neonatal aspiration syndrome morbidity (6.8%vs1.3%, χ2=22.092, P=0.000) in CD group were significantly higher than VD group, the RR were5.111(95%CI:2.392-10.922). The rate of neonatal diarrhea (0.6%vs0.3%) was higher in CD group compared with VD group, but had no significantly statistical difference (P=0.604).The rates of neonatal asphyxia showed no statistical significant difference between the two groups (1.8%vs3.1%,%,χ2=1.541, P=0.214). There was no transient tachypnea of the newborn or neonatal respiratory distress syndrome between the two groups. There were17newborns (2.5%) birth weight over4kg in the VD group, which were delivered smoothly. After controlling for potential confounders, the adjusted OR of neonatal aspiration syndrome in the CD group was4.689(95%CI:2.014-10.916), the difference was statistically significant, while the other outcomes were not statistically significant.4Maternal age and BMI were risk factors for nulliparous to choose cesarean delivery for social factors. [Conclusions]1. Although the risk of postpartum hemorrhage was higher in the vaginal delivery compared with cesarean section for social factors, there was no postpartum serious maternal complications and adverse outcomes due to the postpartum hemorrhage, such as DIC, uterine artery embolization, hysterectomy and maternal death, it means that postpartum hemorrhage can be effectively corrected. Postpartum hemorrhage risk should not be the reason for nulliparous to choose cesarean section for social factors.2、Cesarean section for social factors had not experienced the spontaneous onset of labor, it significantly increases the risk of neonatal respiratory morbidity.3、Women with the older age or the higher BMI were more likely to choose cesarean section as their mode of delivery.4、On the normal circumstance, with the correct application of midwifery skills, a part of newborns whose birth weight over4kg can be delivered transvaginal smoothly, at the same time, it also suggests that the technology of prenatal assessment of fatal size needs to be further improved.