The optimal time for the initiation of in vitro fertilization and embryo transfer among women with atypical endometrial hyperplasia and endometrial carcinoma receiving fertility-sparing treatment

To explore the optimal time for initiating in vitro fertilization and embryo transfer (IVF-ET) in women with complete remission after fertility-sparing treatment for grade I endometrial cancer (EC) or atypical endometrial hyperplasia (AEH).Young women who demonstrated complete remission after fertility-sparing treatment for grade I EC or AEH and underwent IVF-ET treatment were included. A generalized estimating equation (GEE) was used to compare the outcomes of controlled ovarian hyperstimulation (COH) and embryo transfer at different times after discontinuing high-dose progesterone therapy, and patients were divided into three groups: ≤ 3 months (time 1), 3-9 months (time 2) and > 9 months (time 3).Thirty-seven women with complete remission after fertility-sparing treatment for grade I EC or AEH underwent 75 IVF-ET cycles. Regarding initiation of COH, 10 cycles for time 1, 31 cycles for time 2 and 34 cycles for time 3 were included. The odds ratios (95% confidence intervals) for the number of available embryos at time 2 and time 3 were 1.82 (1.08-3.08) and 2.45 (1.39-4.33), and those for the number of high-quality embryos at time 2 and time 3 were, respectively, 3.64 (1.34-9.87) and 3.62 (1.10-11.91), compared with that at time 1. Nineteen (51.4%) women had at least one clinical pregnancy and 13 (35.1%) women had live births. During a median follow-up period of 51 months (range 5-168 months), 10 (27.0%) women had disease relapse, with a median interval of 15.5 months (range 5-104 months).Initiating IVF-ET 3 months after ceasing high-dose progesterone therapy can lead to better outcomes of controlled ovarian hyperstimulation for women with endometrial cancer or atypical endometrial hyperplasia.