A rare case of unicornuate uterus with cervicovaginal agenesis

A 16-year-old female came to the Department of Gynaecology with the chief complaint of periodic lower abdominal pain for two years. She had a history of primary amenorrhea. Secondary sexual characteristics were typical for age. On pelvic examination, the vaginal orifice was absent. Hormonal assays were within normal limits.

Ultrasonography of the pelvis (Figures 1a, 1b and 1c) revealed a unicornuate uterus. The cervix was absent. There was a right ovarian cyst. The left ovary was normal. The left tube was dilated. There was minimal ascites.

MRI of the pelvis (Figures 2a, 2b, 2c and 2d) confirmed the unicornuate uterus. There was a minimal haemorrhagic collection in the uterine cavity. The cervix and vagina were absent. The right ovary was bulky (with an approximate volume of 17 cc) and showed a cyst (measuring about 3cm x 2.6cm) with internal haemorrhage. The left ovary was normal. The dilated left tube showed internal haematic content consistent with haematosalpinx. There was minimal ascites.

For this case, the 2013 European Society of Human Reproduction and Embryology (ESHRE) / European Society for Gynaecological Endoscopy (ESGE) classification is U4bC4V4 [1].

Background

The embryological origin of the uterus (including the cervix), fallopian tubes, and upper two-thirds of the vagina is from the Müllerian ducts. The ovaries come from the germ cells, and the lower third of the vagina originates from the sinovaginal bulb. The development of the uterus occurs in three steps. The Müllerian ducts on both sides develop in the first step (organogenesis). The ducts fuse in the second step (fusion). In the third step (septal resorption), the central septum formed during fusion undergoes resorption. The type of anomaly depends on when a disturbance occurs during embryological development. If the first step does not occur as usual or fails to happen, it may result in agenesis or hypoplasia of the uterus or unicornuate uterus. Failure of the second step may cause bicornuate or uterus didelphys. Septate or arcuate uterus occurs when the third step fails to happen [2].

Clinical Perspective

The present case is unusual due to the complete lack of the vagina, suggesting that the developmental disruption impacted both the upper and lower portions of the vagina, which have distinct origins embryologically. The incidence of cervicovaginal agenesis is 1 in 80,000 to 100,000 live births [3].

The patient’s cyclic abdominal pain and haemorrhagic uterine collection suggest a functioning endometrium within the unicornuate uterus. Menstrual blood could not pass out due to cervicovaginal agenesis, and haematometra and haematosalpinx developed as a complication.

Imaging Perspective

• Ultrasound: A unicornuate uterus appears off-midline and tapers superiorly to one side.
• MRI: The uterus appears asymmetric and fusiform in shape. The uterine size seems diminished.
• Hysterosalpingography: Though not applicable in our patient, it shows a banana-shaped uterus connected to a single fallopian tube.

Outcome

Management of such a case involves surgery for the creation of a neovagina and subsequent anastomosis of the unicornuate uterus with the neovagina. However, the patient has not returned to the Gynaecology Department for a follow-up consultation.

Take Home Message / Teaching Points

In all patients with primary amenorrhea who show uterine malformation on imaging, a careful evaluation of the cervix, vagina, and fallopian tubes is necessary to enable accurate delineation of the spectrum of anomalies and guide patient management.

All patient data have been completely anonymised throughout the entire manuscript and related files.