Effect Of Cesarean Incision Formed Diverticulum On Clinical Outcomes Of Assisted Reproductive Technology

Background: Over the years cesarean section rate has been high in China,with the comprehensive opening of the two-child policy in 2016,there are more and more women of childbearing age who need to have a second child after the previous cesarean section,resulting in a significant increase in the number of cesarean section patients seeking assisted reproductive technology to reproduce.Cesarean section is an important and effective treatment for poor delivery,high-risk pregnancy and other obstetric complications.However,cesarean section also brings many complications,among which the most common one is cesarean scar defect,also known as previous cesarean scar defect.In order to improve the clinical pregnancy rate,assisted reproductive technology tends to increase the number of transplanted embryos,leading to a significantly higher incidence of multiple pregnancies among patients receiving IVF assisted pregnancy than those with natural pregnancy.However,multiple pregnancies bring serious risks of maternal safety and offspring,especially for patients with cesarean scar defect after cesarean section,and the risk of second pregnancy such as multiple pregnancies is even more serious.The ultimate goal of assisted reproductive therapy is to reduce the risk of multiple pregnancies on the basis of ensuring the success rate,and reducing the number of transplanted embryos is to reduce the risk of multiple pregnancies from the perspective of prevention.In particular,single embryo transplantation is particularly important for patients with diverticulum with incision after cesarean section.At present,there are few studies on the efficacy of ART assisted treatment for infertile patients who have a history of cesarean section.However,how to improve the efficacy of ART assisted pregnancy treatment for women who give birth again after previous cesarean section and reduce complications during pregnancy and perinatal period are currently the problems faced by reproductive doctors in clinical work.Objective: The purpose of this study was to explore whether the cesarean scar defect after previous cesarean section surgery affected the clinical outcome of assisted reproductive treatment.How to improve the success rate of assisted reproductive technology in patients with cesarean scar defect after previous cesarean section while reducing the complications during pregnancy and perinatal period brought by multiple pregnancies,thus providing an effective and safe clinical basis for patients with previous cesarean section surgery combined with cesarean scar defect to seek ART treatment.Methods: A retrospective study of 505 IVF/ICSI-ET cycles in the Reproductive Medicine Center of Shenzhen Zhongshan Urology Hospital from January1,2017 to December 31,2018.According to the different delivery modes,they were divided into the vaginal delivery history group(n=271)and the cesarean delivery group(n=234).The cesarean section group was divided into two groups according to whether there was a cesarean scar defect or not,cesarean scar defect(n=64),non-cesarean scar defect(n=170).The cesarean section group can be divided single blastocyst stage embryo transfer(n=56)and double cleavage stage embryo transfer(n52).The main outcome measures include clinical pregnancy rate,multiple pregnancy rate.Secondary outcome measures include biochemical pregnancy rate,abortion rate,multiple pregnancy reduction rate,preterm birth rate.Results:1.The biochemical pregnancy rate,clinical pregnancy rate and embryo implantation rate of the vaginal history group were all higher than those of the patients combined with cesarean scar defect after cesarean section(P < 0.05),but there was no significant difference in pregnancy outcome compared with the group without cesarean scar defect formation after cesarean section(P > 0.05).The incidence of cesarean section delivery in women with previous cesarean section pregnancy was much higher than that in women with previous vaginal delivery(P < 0.05).The probability of placenta previa during the second pregnancy with a history of cesarean section was higher than that with a history of vaginal delivery(P < 0.05).2.Women with a history of cesarean section were more likely to have a cesarean section during the second pregnancy than women with a history of vaginal delivery(P <0.05).3.The early abortion rate of the group with cesarean scar defect formation after cesarean section was higher than that of the group with transvaginal delivery and the group without cesarean scar defect formation after cesarean section(P < 0.05).4.The incidence of placenta previa in the second pregnancy after cesarean section combined with cesarean scar defect was higher than that in the previous vaginal delivery and the group without cesarean scar defect after cesarean section(P < 0.05).5.The biochemical pregnancy rate,clinical pregnancy rate and embryo implantation rate of the group with single blastocyst were higher than that of the group with two Cleavage stage embryo after cesarean section(P < 0.05).6.The multiple pregnancy rate in the group with 1 blastocyst was lower than that of the group with two Cleavage stage embryo after cesarean section(P < 0.05).Conclusions:1.The history of cesarean section surgery itself does not affect the clinical outcome of assisted reproductive pregnancy,but the combination of uterine incision diverticulum formation after cesarean section will reduce the clinical outcome of assisted reproductive pregnancy;Increased perinatal complications during the second pregnancy;2.For patients aged <35 years old with cesarean section who underwent assisted reproduction and assisted gestation embryo transplantation,the rate of pregnancy was higher with the transfer of one blastocyst than that with two cleavage stage embryo,and the incidence of multiple pregnancies was effectively reduced.