Impact of intrauterine fluid accumulation on embryo transfer outcomes among patients with previous cesarean section.

OBJECTIVE

To investigate the impact of intrauterine fluid accumulation (IUF) and cesarean section diverticulum (CSD) on embryo transfer outcomes among patients with a history of cesarean section.

METHODS

This study retrospectively analyzed embryo transfer cycles of infertile patients with previous cesarean delivery, who underwent embryo transfer and hysteroscopic evaluation of cesarean section scar at the Reproductive Center of Peking University Third Hospital, from January 2020 to December 2022. According to results of transvaginal ultrasound during the above time range, the patients were divided into IUF group and non-IUF group. Propensity score matching (PSM) was performed (1:2 ratio) to adjust for confounders. Fertility outcomes including clinical pregnancy rate, live birth rate were compared between the two groups.

RESULTS

After PSM, there were 313 cycles in IUF group and 625 cycles in control group. Compared with non-IUF group, clinical pregnancy rate (28.43 % vs 39.36 %, p < 0.001) and live birth rate (17.89 % vs 27.52 %, p < 0.001) were significantly lower in IUF group. Logistic regression showed that cesarean scar diverticulum had no significant effect on clinical pregnancy rate and live birth rate. Subgroup analysis was further conducted in IUF group, according to whether IUF was found during the transfer cycle. The results showed that clinical pregnancy rate and live birth rate were not statistically different between the two subgroups.

CONCLUSION

IUF is an independent risk factor for reduced fertility outcomes in infertile women with a history of cesarean section. Even transient IUF signifies adverse outcomes of embryo transfer in patients with a prior cesarean section.