Urethral Diverticulum Presenting as a Large Vaginal Mass Complicating Pregnancy and Delivery

BACKGROUND A case report of urethral diverticulum complicating pregnancy is presented. The diagnosis and management are challenging because of the rare nature of this condition, the varied presentations and differential diagnoses, and the possibility of misdiagnosis. CASE REPORT A 25-year-old primigravida with scheduled induction of labor at 39 weeks gestation due to gestational diabetes mellitus presented for a routine antenatal appointment at 38 weeks and four days. On digital cervical examination, she was found to have a large semi-solid anterior vaginal mass, shown by trans-vaginal ultrasound to have a nearly solid appearance of a 5×7 cm mass with septation. Maternal Fetal Medicine and Gynecologic Oncology consultations were obtained primary cesarean section with vaginal biopsy in the Operating Room were recommended. Following an uncomplicated cesarean delivery and with the patient still under spinal anesthesia, the anterior vaginal mass was examined and found to contain 200 ml of purulent material. Because a diagnosis of urethral diverticulum was made, a biopsy was not performed. The patient was placed on antibiotic prophylaxis for the remainder of her hospital course. Follow-up CT scan confirmed a large urethral diverticulum, and she was referred to the Fetal Pelvic Medicine and Reconstructive Surgery (FPMRS) and Urogynecology units for treatment. CONCLUSIONS Early identification of urethral diverticulum during the pregnancy may allow for treatment and a trial of labor with vaginal delivery. MRI is the recommended imaging modality in identifying urethral diverticulum.