An unusual anatomic variation of a unicornuate uterus with normal external uterine morphology

OBJECTIVE: To describe a case of a unicornuate uterus with a normal external uterine morphology. DESIGN: Case report. SETTING: University-based fertility center. PATIENT(S): A 30-year-old nulligravid woman with a 1-year history of infertility found to have a right proximal tubal occlusion on hysterosalpingogram. INTERVENTION(S): Laparoscopy, hysteroscopy, and magnetic resonance imaging. MAIN OUTCOME MEASURE(S): External and internal morphology of the uterus. RESULT(S): Laparoscopy showed a normal external uterine morphology and normal fallopian tubes and ovaries, but chromopertubation failed to demonstrate a fill and spill from the right fallopian tube. Hysteroscopy showed a single tubular uterine cavity projecting to the left with a single left tubal ostium, consistent with a unicornuate uterus. Magnetic resonance imaging confirmed a normal external uterine fundal contour and an internal uterine morphology consistent with a unicornuate uterus. CONCLUSION(S): This is the first reported case of a unicornuate uterus presenting with a normal external uterine morphology and an internal morphology consistent with a unicornuate uterus, and we propose inclusion of this anomaly in the classification of mullerian anomalies.