Diagnostic Ultrasound - Abdomen and Pelvis

Uterine Anomalies
Diagnoses: Female Pelvis
American Fertility Society Classification System of Müllerian Duct Anomalies
Category Type Definition
Class I Agenesis or hypoplasia Complete or segmental agenesis, or variable uterovaginal hypoplasia
Class II Unicornuate uterus Partial or complete unilateral hypoplasia
Class III Uterus didelphys Duplication of uterus
Class IV Bicornuate uterus Incomplete fusion of superior uterovaginal canal
Class V Septate uterus Incomplete resorption of uterine septum
Class VI Arcuate uterus Near complete resorption of uterine septum/normal variant
Class VII T-shaped uterus In utero Diethylstilbestrol (DES) exposure
(The American Fertility Society classification system is the most widely utilized and accepted.
The American Fertility Society classifications of adnexal adhesions, distal tubal occlusion, tubal occlusion secondary to tubal ligation, tubal
pregnancies, müllerian anomalies and intrauterine adhesions. Fertil Steril. 49(6):944-55, 1988)
○ Müllerian duct structures
– Fallopian tubes, uterus, cervix, upper 2/3 of vagina
○ MDAs occur during 1 of 3 phases of development
– Organogenesis phase: Uterine agenesis, hypoplasia,
unicornuate
– Fusion phase: Didelphys, bicornuate
– Septal resorption phase: Septate, arcuate
• Associated abnormalities
○ Renal anomalies in 30-50%
– Renal agenesis most common
– Ectopic kidney, horseshoe kidney, duplicated
collecting system, renal dysplasia also possible
○ Endometriosis if obstruction present
○ Mayer-Rokitansky-Kuster-Hauser syndrome
– Most common etiology of class I MDA
– Complete vaginal agenesis
– 90% have uterine agenesis; 10% with rudimentary
horn
○ Obstructed hemivagina-ipsilateral renal agenesis
(OHVIRA)
– Associated with class III MDA
– Unilateral obstructing transverse vaginal septum →
hematometrocolpos
– Ipsilateral renal agenesis
CLINICAL ISSUES
Presentation
• Most common signs/symptoms
○ Asymptomatic
○ Presents at menarche
– Primary amenorrhea or dysmenorrhea
– Uterus didelphys → duplicated vagina → normal
menses through unobstructed side with progressive
distension of obstructed side
○ Obstetric-/fertility-related
– Recurrent spontaneous abortions/infertility
– Malpresentation, premature labor, intrauterine
growth restriction
– Ectopic pregnancy
• Other signs/symptoms
○ Cyclical pelvic pain and pressure
○ Distended uterus/vagina → mass effect → acute urinary
retention
Demographics
• Epidemiology
○ 1-5% prevalence in general population
– Up to 25% in women with recurrent pregnancy loss
and infertility
– Prevalence of subtypes depends on method of
diagnosis and patient population
○ Vaginal agenesis = 1:5,000
Natural History & Prognosis
• Depends on underlying malformation
• Associated with endometriosis if obstruction
○ Increased incidence of infertility/ectopic pregnancy
○ Chronic pelvic pain
Treatment
• MR to verify diagnosis and assess extent of associated
malformation
• MDA repair varies with malformation
○ Simple septal resection to more complex vaginal
reconstruction
○ Creation of perineal opening/vaginoplasty
○ Uterine surgery may be required to improve chances of
successful pregnancy
DIAGNOSTIC CHECKLIST
Consider
• MDA in patients with recurrent miscarriage or infertility
• HM/HC should be evaluated for in any young female with
cyclical pelvic pain
• Image renal fossae to assess for unilateral agenesis
Image Interpretation Pearls
• Determining outer uterine contour is essential to
distinguish septate vs. bicornuate uterus
• Determine presence of communication between
endometrial cavities
• Determine if 1 or 2 cervices
SELECTED REFERENCES
1. Sakhel K et al: Begin with the basics: role of 3-dimensional sonography as a
first-line imaging technique in the cost-effective evaluation of gynecologic
pelvic disease. J Ultrasound Med. 32(3):381-8, 2013
2. Behr SC et al: Imaging of müllerian duct anomalies. Radiographics.
32(6):E233-50, 2012
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