P-327 Intrauterine fluid in patients with cesarean section defects in association with ivf outcomes

Abstract Study question This study evaluate the effect of cesarean section scar defects associated with intrauterine fluid during endometrial preparation on pregnancy outcomes. Summary answer Patients with Cesarean section scar defect and intrauterine fluid during endometrial preparation had a substantially lower pregnancy outcome compared to those without uterine fluid. What is known already The Cesarean section rate in developed countries has increased continuously, leaving many short-term and long-term consequences. Intrauterine fluid, which reported incidence may reach 40% in patients who have had a previous caesarean section, may play an important role in reducing endometrial receptivity and further impair pregnancy outcomes. Study design, size, duration This is a retrospective cohort study performed on patients who had undergone frozen embryo transfer at an Assisted Reproductive Technology Center from January 2019 to December 2019. Participants/materials, setting, methods 2,350 patients without intrauterine fluid and 74 patients with Cesarean section scar defect who had intrauterine fluid during endometrial preparation but none at progesterone supplementation were analyzed. Multiple logistic regression was performed for the probability of the pregnancy outcome of embryo transfer and measured the association with the status of intrauterine fluid, age, endometrial thickness, number of previous transfer, number of embryos, type of infertility, and difficult embryo transfer at the alpha level of 0.05%. Main results and the role of chance The outcomes among 2,424 patients undergoing cryopreserved embryo transfer were 59.45% for pregnancy rate, 8.7% for biochemical pregnancy rate, 50.33% for clinical pregnancy rate, and 43.15% for ongoing pregnancy rate. The analysis of multiple logistic regression indicated that the presence of intrauterine fluid during endometrial preparation did not affect the pregnancy rate. However, in patients with intrauterine fluid, there was an increased rate of biochemical pregnancy (OR 2.46, 95%CI 1.35-4.50) and a reduced rate of ongoing pregnancy (OR 0.54, 95%CI 0.32-0.89). Limitations, reasons for caution The major limitations of the present study are the retrospective design and small number of patients with uterine fluid. Additionally, the composition of the uterine fluid (eg, blood, mucus, purulent, or transparent) cannot be classified by an ultrasound exam. Wider implications of the findings Intrauterine fluid may be an innovative and controllable factor that should be considered in patients who have a history of caesarean section in order to improve pregnancy outcomes. Trial registration number Not Applicable