Retroflexion of the uterus

POP-Q Classification and Anatomical Landmarks

The international POP-Q (Pelvic Organ Prolapse Quantification) classification allows for precise determination of the degree of pelvic organ prolapse. The method is based on measuring 9 anatomical parameters (points and distances) relative to the hymenal ring:

• Anterior compartment: points Aa (urethrovesical segment) and Ba (anterior vaginal wall).
• Apical compartment: point C (cervix or vaginal cuff) and point D (posterior vaginal fornix).
• Posterior compartment: point Ap (lower posterior vaginal wall) and Bp (above the levators).
• Hiatus and perineum: GH (genital hiatus from the urethral meatus to the posterior hymenal ring) and PB (perineal body from the posterior hymenal ring to the mid-anal verge).
• Axis: TVL (total vaginal length).

Stages of Pelvic Organ Prolapse

Based on measurements using the POP-Q system, several stages of descent and prolapse are distinguished:

1. Stage 0: no prolapse. Points Aa, Ap, Ba, Bp are all at -3 cm, and points C and D are between TVL and (TVL - 2 cm) with a negative sign.
2. Stage I: the most distal portion of the prolapse is more than 1 cm above the hymen (< -1 cm).
3. Stage II: the most distal portion of the prolapse is less than or equal to 1 cm proximal or distal to the hymen (> -1 cm and < +1 cm).
4. Stage III: the prolapse extends more than 1 cm below the hymenal plane, but no further than 2 cm less than the total vaginal length.
5. Stage IV: complete procidentia, where the most distal portion protrudes further than TVL — 2 cm.

Etiology, Pathogenesis, and Risk Factors

Pelvic organ descent and prolapse is a multi-etiological condition. The primary cause is pelvic fascia rupture caused by connective tissue pathology. Contributing factors include pelvic floor muscle insufficiency and increased intra-abdominal pressure.

The anatomical basis relies on DeLancey's three-level theory of pelvic organ support. The following groups of risk factors are identified:

• Traumatic childbirth: macrosomia, repeated and prolonged labor, vaginal surgeries, and perineal tears.
• Systemic deficiency: connective tissue dysplasia manifesting as hernias in other locations.
• Hormonal disorders: estrogen deficiency due to impaired steroid hormone synthesis.
• Chronic diseases: metabolic and microcirculatory disorders.

Clinical presentation

The pathology develops slowly and progressively. The leading symptom is the patient discovering a "foreign body" outside the vagina, which is most characteristic of uterine and vaginal wall prolapse.

Due to constant prolapse, the mucous membrane of the genital surface eventually undergoes keratinization under the influence of external factors.

Class and exam questions

What else to study on this topic

• Post-hysterectomy prolapses and characteristics of vaginal cuff descent
• Detailed analysis of DeLancey's three-level theory of pelvic organ support
• Instrumental methods for measuring points Aa, Ba, Ap, Bp, C, D in clinical practice
• The effect of estrogen deficiency on the connective tissue of the pelvic floor
• Pathomorphological changes of the mucous membrane during keratinization

Other topics in the "Gynecology" section

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