Endometrial Fibroid Fistula Formation after Uterine Fibroid Embolization: A Case Report

Abstract Uterine fibroids are benign tumors that originate from the smooth muscle of the uterus. They are often associated with menorrhagia, pelvic pain, infertility, and a sensation of pressure. The symptoms depend on the location of the fibroids, with submucosal fibroids more commonly causing menorrhagia due to their proximity to the endometrium. Meanwhile, intramural and subserosal fibroids typically do not cause excessive bleeding unless they disrupt the endometrial lining. Uterine Fibroid embolization (UFE) is a minimally invasive treatment for fibroids that works by occluding the arteries supplying the fibroids, leading to ischemic necrosis and fibroid shrinkage. This case report describes a 40-year-old female who presented with heavy menstrual bleeding, pelvic pain, and increased urinary frequency due to an endometrial uterine fibroid - for which she underwent a UFE. Follow-up at 3.5 months post-UFE revealed reduced uterine size and menstrual symptom improvement. At one year post-procedure, the patient developed increased pelvic pressure and heavier bleeding compared to her post-UFE baseline. MRI obtained 9 months later displayed a reduction in the size of the fundal fibroid. A new finding of a fistula between this fundal fibroid and the endometrial canal was also observed and confirmed with an in-office hysteroscopy. Conservative management, including iron supplementation, pain control, and serial ultrasound monitoring, resulted in symptom resolution within two weeks.