• Clinical science

Anomalies of the female genital tract

Abstract


Structural anomalies of the female genital tract may be present at birth or may be acquired later in life. Common congenital anomalies of the female genital tract are an imperforate hymen and anomalies of Müllerian duct fusion. Impaired fusion of the Müllerian ducts can result in duplication of the uterus, cervix, and/or vagina, while incomplete fusion results in an intrauterine and/or intravaginal septum. Rarely, the Müllerian duct may be completely absent (Müllerian agenesis), resulting in the absence of the uterus, cervix, and vagina. Acquired structural anomalies include intrauterine adhesions and labial fusion. Intrauterine adhesions occur following uterine curettage or as a result of pelvic inflammatory disease. Labial fusion is the result of estrogen deficiency during childhood. Most patients with structural anomalies of the female genital tract remain asymptomatic until puberty. While Müllerian agenesis, labial fusion, and an imperforate hymen present with primary amenorrhea, intrauterine adhesions present with secondary amenorrhea. Infertility may be the initial symptom in all structural anomalies of the genital tract. The diagnoses of imperforate hymen and labial fusion are primarily clinical. Structural anomalies of the uterus and cervix are diagnosed with imaging such as a transvaginal ultrasonography. Surgical reconstruction or resection is the main treatment for both the congenital and acquired genital tract anomalies. Labial fusion is treated with topical estrogen.

Anomalies of the uterus

Anomalies of Müllerian duct fusion

Anomalies of Müllerian duct fusion
Types of fusion anomalies Relative frequency Pathophysiology

Müllerian agenesis (Class I)

Rare Both the Müllerian ducts fail to develop → absent or hypoplastic uterus, absent cervix, and vaginal atresia
Unicornuate uterus (Class II) 10% One of the Müllerian ducts fails to develop
Didelphic uterus (Class III) 8% Complete lack of Müllerian duct fusion → double uterus, double cervix, double vagina
Bicornuate uterus (Class IV) 26%

Incomplete fusion of the Müllerian ducts to various degrees

  • Uterus bicornis unicollis: double uterus, single cervix, and single vagina
  • Uterus bicornis bicollis: double uterus and double cervix with/without a vaginal septum
Septate uterus (Class V) 35% The Müllerian ducts fuse, but the septa between the two ducts persists either partially (subseptate uterus) or completely (septate uterus).
Arcuate uterus (Class VI) 18% Near complete fusion of the Müllerian ducts but the cornua of the fundus remain separate → concave uterine fundus with a heart-shaped uterine cavity

DES-related abnormality (Class VII)

Rare

In-utero exposure to diethylstilbestrol

The mere presence of a Müllerian duct anomaly is not an indication for surgical therapy. In a patient with infertility and congenital uterine anomalies, it is important to rule out other causes of infertility before surgical therapy is considered!

Intrauterine adhesions (Asherman syndrome)

  • Etiology
    • Following uterine curettage (most common cause)
    • Postinflammatory; (e.g., chlamydia and rarely tuberculosis)
  • Clinical features
  • Diagnostics
    • Progesterone withdrawal test: bleeding does not occur following progestin withdrawal given block of outflow track
    • Hysterosalpingography: honeycomb appearance of the uterus
    • Confirmatory test: hysteroscopy to directly visualize adhesions
  • Treatment
    • Hysteroscopic resection of the adhesions
    • Treatment is only indicated if patients are symptomatic.

References:[1][2][3][4]

Anomalies of the vulva and vagina

Imperforate hymen

  • Definition: a hymen without an opening
  • Etiology: congenital defect
  • Incidence: 1/2000 females
  • Pathophysiology: : central cells of the Müllerian eminence in the urogenital sinus do not disintegrate → imperforate hymen cryptomenorrhea at puberty (outflow tract obstruction leads to backup of menstrual blood) hematocolpos
  • Clinical features
    • Asymptomatic before puberty
    • Primary amenorrhea with periodic lower abdominal pain
    • Possible urinary retention, frequency, dysuria
    • Possible palpable lower abdominal mass
    • Perineal examination: tense, bulging, bluish membrane in the vulva
  • Diagnostics: primarily a clinical diagnosis
  • Treatment: excision of the imperforate hymen (hymenectomy)

Vaginal atresia

Transverse vaginal septum

  • Incidence: 1/70,000 females
  • Pathophysiology
    • Failure of recanalization of the Müllerian duct → transverse septum in the upper-third (45%), lower third (15–20%), and/or middle third (35–40%) of the vagina
    • Associated with cervical hypoplasia or absence
    • Cryptomenorrheahematocolpos
  • Clinical features
  • Diagnostics: transvaginal ultrasonography or MRI
  • Treatment
    • First-line: nonsurgical dilation over 6–12 months using graduated vaginal dilators
    • Second-line: vaginoplasty

Labial fusion

  • Definition: partial or complete adhesion of the labia minora
  • Epidemiology: occurs in 2–5% of females up to 4 years of age
  • Etiology:
    • Absence of estrogen → predisposition to mild infection local inflammation → raw surface epithelium of the labia minora → adhesions
    • In rare cases: trauma (sexual abuse), congenital defect
  • Pathophysiology
    • Adhesions form in posterior to anterior direction, leaving an opening for the external urethral meatus.
    • In the case of complete labial fusion, the urethral opening is also obstructed.
  • Clinical features
    • Usually asymptomatic
    • If external urethral opening is obstructed: recurrent attacks of UTI, vaginitis, vestibulitis
    • Perineal examination
      • A thin vertical midline fold in the perineum
      • The labia, vaginal opening, and occasionally the urethral meatus are not visible.
  • Diagnostics: : primarily clinical diagnosis
  • Treatment:
    • Application of topical estrogen
    • If the external urethral opening is obstructed:
      1. Manual separation of the the adhesions using fingers or a probe
      2. Application of topical estrogen on the denuded surface

References:[5][6][7][8][9][10]