Obstructed ureterovaginal anomalies may present in the neonate, however the majority present with the accumulation of menstrual blood at menarche. These anomalies are classified into three groups:

1. Agenesis of the uterus and most/all of the vagina (lower 1/3 usually present because it is derived from the urogenital sinus), known as Mayer-Rokitansky-Kuster-Hauser Syndrome (MRKHS). Hematometros (blood within the endometrial cavity) or hematometrocolpos (blood within the vagina and endometrial cavity) results if a uterine anlage (Müllerian duct remnant) is present.
   
2. The descending Müllerian ducts can fail to fuse with the ascending urogenital sinus, resulting in hematometrocolpos from a vaginal septum.  Hematometra can occur with an imperforate cervix, cervical agenesis, or vaginal agenesis with a normal uterus.  A transverse vaginal septum is most common cause and is usually located at the junction of upper/middle third of the vagina.
   
3. Disorders of lateral fusion result in duplication anomalies with vaginal obstruction, most commonly occurring with a uterus didelphys. Unilateral obstruction can be difficult diagnosis because there is "normal menses" flow from the unobstructed side.  Signs and symptoms include a bulging hymen, an intralabial mass (low vaginal obstruction), an abdominal mass, cyclic abdominal pain, primary amenorrhea, voiding dysfunction, or ambiguous genitalia.

Ultrasound and MRI are comparable for diagnosis, but MRI is superior at characterization of the underlying cause due to multiplanar capability and soft tissue resolution.  MRI is particularly useful for MRKHS and disorders of lateral fusion. Ultrasound can differentiate between uterine and vaginal involvement, and ultrasound identifies hematosalpinx, which increases the risk for developing endometriosis. Also, ultrasound can evaluate the presence and patency of the cervix. With cervical agenesis, the vagina tapers to a blind pouch. When hematometra is present, nonvisualization of the (fluid-filled) endocervical canal means the cervix is imperforate. Ultrasound also can detect renal anomalies (associated with genital anomalies) and evaluate for complications of delayed diagnosis (hydronephrosis and endometriosis).

1.  Scanlan KA, Pozniak MA, Fagerholm M, Shapiro S. Value of transperineal sonography in the assessment of vaginal atresia. AJR 1990;154(3):545-8.

2.  Woodward PJ, et al. Congenital uterine malformations. Current Problems in Diagnostic Radiology 1995; 24(5):178-97.

3.  Blask AR, Sanders RC, Rock JA. Obstructed ureterovaginal anomalies: demonstration with ultrasound. Part II. teenagers. Radiology 1991; 179(1):84-8.

4.  Moore KL, Persaud TVN. Before we are born: essentials of embryology and birth defects. 4th edition. 1993. p. 217.

Modality: US    Pathology: Congenital    Anatomy: Genitourinary (GU)