Fertility-Sparing Treatment and Assisted Reproductive Technology in Patients with Endometrial Carcinoma and Endometrial Hyperplasia: Pregnancy Outcomes after Embryo Transfer.

The goal of fertility-sparing treatment (FST) for patients desiring future fertility with EMCA, and its precursor EH, is to clear the affected tissue and revert to normal endometrial function. Approximately 15% of patients treated with FST will have a live birth without the need for assisted reproductive technology (ART). Despite this low number, little information exists on the pregnancy outcomes of patients who utilize ART. The purpose of this study was to evaluate pregnancy outcomes following embryo transfer in patients with EMCA or EH who elected for FST. This retrospective cohort study at a large urban university-affiliated fertility center included all patients who underwent embryo transfer after fertility-sparing treatment for EMCA or EH between January 2003 and December 2018. Primary outcomes included embryo transfer results and a live birth rate (defined as the number of live births per number of transfers). There were 14 patients, three with EMCA and 11 with EH, who met the criteria for inclusion with a combined total of 40 embryo transfers. An analysis of observed outcomes by sub-group, compared to the expected outcomes at our center (patients without EMCA/EH matched for age, embryo transfer type and number, and utilization of PGT-A) showed that patients with EMCA/EH after FST had a significantly lower live birth rate than expected (Z = -5.04, df = 39, < 0.01). A sub-group analysis of the 14 euploid embryo transfers resulted in a live birth rate of 21.4% compared to an expected rate of 62.8% (Z = -3.32, df = 13, < 0.001). Among patients with EMCA/EH who required assisted reproductive technology, live birth rates were lower than expected following embryo transfer when compared to patients without EMCA/EH at our center. Further evaluation of the impact of the diagnosis, treatment, and repeated cavity instrumentation for FST is necessary to create an individualized and optimized approach for this unique patient population.