This study aimed to present cases involving in vitro fertilization (IVF) cycles in patients with stage IA endometrial adenocarcinoma (EC) who underwent fertility-sparing conservative treatment. Twenty-two patients who underwent IVF cycles in a single fertility center between May 2005 and February 2017 after progestin treatment for stage IA EC were chosen for this study. Outcomes of IVF cycles were analyzed retrospectively. Women of a median age of 34years (range 26-41years) underwent a total of 49 embryo transfers within an average of 2months after their last progestin treatment. The clinical pregnancy rate per transfer was 26.5%, implantation rate was 16.7%, and live birth rate was 14.3%. The cumulative clinical pregnancy rate was 50% (11/22), resulting in 6 live births (27.3%) within 3 cycles of embryo transfer. The median endometrial thickness on the day of human chorionic gonadotropin injection in 34 fresh cycles was 9.0mm (range 4-10mm) in live births, 7.5mm (range 6-9mm) in miscarriages, and 6.0mm (range 4-15mm) in no pregnancy cases. During a median post-cancer treatment follow-up period of 41months (range9-150months), 6 (27.3%) women underwent definitive hysterectomy for EC relapse. This study showed an acceptable cumulative pregnancy rate after the IVF procedure in patients with early-stage EC who were treated conservatively. Considering the high relapse rate, it is of great importance that these patients are closely monitored after the IVF cycles.