Conservative treatment with high doses of progestin is an alternative to standard hysterectomy for young patients with early-stage endometrial adenocarcinoma who desire to preserve their fertility. Here we report a patient with well-differentiated early-stage endometrial adenocarcinoma and poor fertility potential who failed to become pregnant in two in vitro fertilization-embryo transfer cycles and suffered a relapse after conservative treatment. This case illustrates that assessment of fertility potential is critical at the time of initial evaluation and conservative treatment planning for patients with endometrial adenocarcinoma.