Endometrial preparation protocols in patients with prior intrauterine adhesion separation surgery

ObjectiveTo investigate the impact of three endometrial preparation protocols-hormone replacement therapy (HRT), natural cycle (NC), and down-regulation HRT-on pregnancy outcomes in frozen embryo transfer (FET) cycles among patients with a history of intrauterine adhesion (IUA) separation surgery.MethodA retrospective cohort study was conducted to analyze the data from FET cycles at reproductive medicine center from January 2017 to December 2023. The patients with a history of intrauterine adhesion separation surgery were classified into three groups: the HRT group (n=285), the NC group (n=200), and the down-regulation HRT group (n=104). Baseline characteristics and reproductive outcomes were compared between the groups. Chi-square tests were used for univariate analysis, and multivariate logistic regression analysis was conducted to adjust for confounding factors.ResultsThere were statistically significant differences among the three groups in terms of general charateristics (all P0.05). Similarly, there were no statistically significant differences in clinical pregnancy rate, biochemical pregnancy rate, live birth rate, and early miscarriage rate between the down-regulation-HRT group and the HRT group (all P>0.05).ConclusionFor patients undergoing FET cycle with a history of IUA separation surgery, the live birth rate is similar between three groups. However, the natural cycle endometrial preparation protocol yielded higher clinical and biochemical pregnancy rates than the HRT protocol, suggesting its potential clinical advantage for these patients.