Genital Tract Outflow Obstruction Clinical Presentation

Updated: Mar 07, 2023
  • Author: Natascha Cecelia Cirignani, DO; Chief Editor: Andrea L Zuckerman, MD  more...
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Although some anomalies (eg, imperforate hymen) can be diagnosed upon gentle inspection with labial separation, most patients go undiagnosed until puberty. Unless the newborn develops a mucocele (a buildup of vaginal secretions that were stimulated by maternal estrogen), the obstruction is not obviously seen on physical exam.   

Once puberty occurs, patients present with history of amenorrhea, recurrent lower abdominal cyclical pain, or lower abdominal midline mass. [12] An obstructive anomaly should be part of the differential diagnosis when a patient presents with primary amenorrhea but normal secondary sexual characteristics. With normal puberty, menses is expected 2-3 years after breast bud development. [3]  A workup for primary amenorrhea is indicated in any patient with secondary sexual characteristics and no menses by age 15 years or by 3 years after breast development. 

Even when a patient presents with monthly menstrual flow, the clinician should still be suspicious for an obstructive anomaly. There are duplicate-system disorders (eg, obstructive hemivagina and ipsilateral renal agenesis [OHVIRA] syndrome [also known as Herlyn-Werner-Wunderlich syndrome] and rudimentary uterine horn) in which an obstruction causes cyclical pain while normal unobstructed menstrual flow still occurs via a separate system.


Physical Examination

Physical examination findings vary according to the level of the obstruction (see Levels of Outflow Obstruction below). Some obstructions may not even be visualizable without imaging.

In cases involving imperforate hymen or certain transverse vaginal septa, obstructions can be seen in the office upon gentle examination. Given that these patients are young and this is usually their first vaginal examination, it is vital to ensure their comfort and give them some control over the situation. Often, they are most comfortable when placed in a frog-leg position with a sheet covering to allow them to decide when they are ready to have the sheet lifted. If menstruation has occurred and hematocolpos developed, the hymen or vaginal septum may bulge and exhibit a bluish discoloration. [1]  On occasion, it can be helpful to have the patient perform a Valsalva maneuver to enable better visualization of a bulge. 

On physical examination, it is important to differentiate an imperforate hymen from a transverse vaginal septum; the two conditions are managed differently. A transverse vaginal septum will be present cephalad to a hymenal ring. It can be found anywhere along the vaginal canal, in the lower, middle, or upper portion. [13]  A knee-chest examination position is sometimes better for visualizing the presence of a bulging septum, especially when it is in the upper third of the canal. If the patient is old enough, digital examination can help identify a septum that is difficult to see. If an obstruction cannot be visualized on examination but is suspected on the basis of the history, appropriate imaging should be ordered.  


Levels of Outflow Obstruction

Obstruction of menstrual flow can occur at any place between the endometrium and the hymen. To determine the necessary treatment (see Treatment), one must accurately diagnose the anomaly present. The following sections list different outflow obstructions according to the level at which the obstruction occurs, proceeding from cephalad to caudad.  


Rudimentary uterine horn  

Rudimentary uterine horn is a consequence of failed fusion of the paired müllerian ducts. Patients have one normal unicornuate uterus that is connected to the cervix and the vagina, along with a smaller separate rudimentary uterus. The rudimentary horn can come in various forms. Some are communicating with the functional uterus, whereas others are separated (ie, noncommunicating). Any noncommunicating rudimentary horn can be obstructive if it has a functional endometrium. These patients present with cyclical abdominal pain but normal menses. If the condition is left undiagnosed, patients will experience severe constant abdominal pain as the menstrual blood builds up in the rudimentary horn. [14]   

Mayer-Rokitansky-Küster-Hauser syndrome 

Mayer-Rokitansky-Küster-Hauser (MRKH) syndrome is the congenital absence of the vagina and uterus resulting from failed fusion of the caudal portion of the müllerian ducts. [4]  It is the second most common cause of primary amenorrhea. [5]  Despite having a blind vaginal pouch, the majority of these patients do not have obstructive symptoms, because they lack an endometrium. This disorder, however, has a spectrum of manifestations, and some patients do have rudimentary müllerian structures with functional endometrium. [6]


Cervical agenesis

Cervical agenesis is a rare anomaly (estimated incidence, 1:80,000) in which the cervix fails to develop. [3]  It can present in a variety of forms, including partial and complete agenesis, and it may occur with or without agenesis of the vagina. [15]

Vaginal canal 

Transverse vaginal septum

Transverse vaginal septum is due either to incomplete canalization of the vaginal plate or to failure of the sinovaginal bulb fails to meet the müllerian ducts. [13]  As mentioned previously, it is vital to differentiate this condition from an imperforate hymen. Both can present with amenorrhea, bulk symptoms, or, if microperforations present, difficulty with tampon insertion or intercourse. [13]  The only means of determining which pathologic condition is present is physical examination.

For appropriate surgical planning, it is important to obtain an accurate assessment of both the location of the transverse septum and its thickness. The location of the septum is determined by measuring its distance from the vaginal introitus: Any septum less than 3 cm cephalad is considered low, and any septum more than 6 cm is considered high. [16]  As for thickness, any septum with a thickness of 1 cm or greater is considered thick for the purposes of surgical planning.

Partial vaginal agenesis

Incomplete atresia of the müllerian duct leads to a shortened vaginal canal internally (which becomes the hematocolpos) and to a blind vaginal pouch externally. On physical examination. no bulge is seen, because the anomaly does not involve the urogenital sinus. The hematocolpos may be palpated abdominally or on rectal examination. [1]

Obstructed hemivagina and ipsilateral renal agenesis syndrome

OHVIRA syndrome is defined by a specific combination of anomalies, as follows [3] :

  • Duplicated reproductive system
  • Obstructed hemivagina
  • Ipsilateral renal anomaly (eg, duplicated ureter, renal agenesis, or dysplastic kidneys)

This syndrome is thought to be the result of faulty or arrested development in the caudal portion of the paramesonephric duct. [3]  Because of the duplicated system, these patients do not present with amenorrhea, and the diagnosis is therefore a challenging one. If OHVIRA is strongly suspected, follow-up with appropriate imaging is essential. In the past, laparoscopy was the only means of diagnosing OHVIRA, but in current practice, magnetic resonance imaging (MRI) is the gold standard. [11]


Imperforate hymen

Contrary to common cultural beliefs regarding the need to “break” the hymen at the time of first intercourse, perforation of the hymen occurs during embryogenesis in normal development. If this perforation does not occur, the patient will need surgical management to open the hymen and allow for menstruation.



Potential complications include the following:

  • Hematocolpos
  • Hematometra
  • Pyohematocolpos
  • Pyohematometra
  • Urinary retention, hydronephrosis (rare)
  • Postoperative recurrence of obstruction
  • Constipation
  • Abdominal mass