Abstract
Introduction
Occurring in 5.5% of the general population, uterine anomalies are the result of abnormalities in the genesis, fusion, and resorption phases of paramesonephric duct development. These abnormalities are more prevalent in women with infertility and recurrent pregnancy loss. Accurate classification can be performed via 3D ultrasound or MRI and is important as management differs among the uterine anomaly types. Although a longitudinal vaginal septum is more commonly associated with abnormalities in the fusion phase that can cause bicornuate and didelphys uterus, it may also rarely occur with a septate uterus.
Case Info
A 34-year-old G0P0 woman with a 10 year history of infertility and ultrasound revealing two endometrial cavities had an MRI of her pelvis. Her MRI demonstrated two endometrial cavities with a complete septum in her uterus and vagina. This vaginal septum initially pointed her diagnosis towards bicornuate or didelphys uterus. However, measurement of the external uterine contour demonstrated a fundal cleft measuring less than 1 cm. This supported a diagnosis of complete longitudinal vaginal septum with complete septate uterus rather than a bicornuate or didelphys uterus. She was offered the option of surgical resection of the septum and chose to defer intervention. She conceived several months later without surgical intervention and was counseled regarding complications associated with a septate uterus.
Disc Clinical
Anchoring on a longitudinal vaginal septum may lead to misdiagnosis of bicornuate or didelphys uterus due to stronger association with these anomalies. MRI allows for measurement of the external fundal contour, fundal cleft, intercornual distance, and endometrial cavity angle, all of which are helpful in classification of the uterine anomaly type. This distinction is clinically important as a septate uterus may be amenable with hysteroscopic septum resection. This is not the case for bicornuate or didelphys uterus as surgical correction would be much more invasive. Additionally, septate uterus has also been associated with an increased risk of spontaneous abortion. For patients with multiple pregnancy losses, accurate diagnosis is particularly important.
Conclusion
Complete longitudinal vaginal septum can occur in association with a septate uterus and should not be considered diagnostic of a uterine fusion anomaly. Careful measurement of radiographic features such as fundal cleft is essential to avoid misclassification and ensure appropriate clinical management.