Pelvic Organ Prolapse and Uterine Support

Pelvic Organ Prolapse (POP)

• POP is a bulge of pelvic organs and their associated vaginal segment into or through the vagina.
• Normally, the external os lies on the level of the ischial spine, and the internal os is at the upper border of the pubic symphysis. Any descent of the uterus from these levels indicates prolapse.

Support of the Uterus

• Primary Supports (Muscular/Active):

  • Pelvic diaphragm: Levator ani muscles (pubococcygeus, iliococcygeus, puborectalis), and ischiococcygeus.
  • Urogenital diaphragm: Superior and inferior fascia of the urogenital diaphragm, deep transverse perinei muscle, and sphincter urethrae muscle.
  • Perineal body: Four sets of paired muscles (superficial transverse perinei, deep transverse perinei, bulbocavernosus). Two unpaired muscles (external anal sphincter, longitudinal muscle fold of rectum and anal canal)

• Secondary Supports (Fibromuscular/Mechanical):

  • Uterine axis (anteversion 90° and anteflexion 120°)
  • Transverse cervical ligament
  • Pubocervical ligament
  • Uterosacral ligament
  • Round ligament

Levels of Vaginal Support

• Level 1: Cardinal and uterosacral ligament attachment to the cervix and upper vagina.
• Level 2: Paravaginal attachment of lateral vagina and endopelvic fascia to the arcus tendinous.
• Level 3: Perineal body, superficial and deep perineal muscles, and fibromuscular connective tissue.

Risk Factors Associated with POP

• Vaginal Birth: Risk is increased 1-2 times with each vaginal delivery.
• Pregnancy: High progesterone level causing pelvic tissue laxity.
• Age: Incidence roughly doubles with each decade between 20-59 years old.
• Menopause: Hyperestrogenism.
• Connective Tissue Disease: Marfan syndrome, Ehlers-Danlos syndrome (ratio of collagen I to collagen III & IV is decreased).
• Race: Hispanics and white women have a higher incidence.
• Chronic Increased Intra-Abdominal Pressure: COPD, chronic constipation, obesity, repeated heavy lifting.
• Pelvic Floor Trauma: Forceps/Vacuum delivery, episiotomy, Spina Bifida Occulta.
• Cigarette Smoking: Can cause a1-antitrypsin deficiency.

Clinical Types of Pelvic Organ Prolapse

• Anterior Wall: Cystocele (upper 2/3 of anterior vaginal wall), urethrocele (lower 1/3 of anterior vaginal wall)
• Posterior Wall: Relaxed perineum (torn perineal body), rectocele (middle 1/3 of posterior vaginal wall), and adjacent rectovaginal septum.
• Vault Prolapse: Enterocele (laxity of the upper third of the posterior vaginal wall, often containing omentum or small bowel loops). Secondary vault prolapse often occurs following hysterectomy.

Clinical Features

• Symptoms: Abdominal or vaginal bulge, pressure, heaviness, incontinence, frequency, urgency, incomplete emptying, straining during bowel movements, dyspareunia, decreased lubrication, sensation, and arousal. Pain in vagina, bladder, rectum, and/or low back pain also possible.

• Diagnosis: Composite examination (visual and physical), general examination (checking BMI and signs of medical conditions), pelvic examinations (bladder emptied, lithotomy position, patient straining), bowel and bladder function evaluation, imaging, and POP-Q staging.

POP-Q Staging System

• Stage 0: No prolapse.
• Stage I: Prolapse is > 1 cm above the hymen.
• Stage II: Prolapse is ≤ 1 cm proximal or distal to hymen.
• Stage III: Prolapse is >1 cm below hymen, but protrudes no further than 2 cm less than total vaginal length.
• Stage IV: Complete eversion of the lower genital tract, at least (TVL -2) cm.

Management of Pelvic Organ Prolapse

• Conservative Management: Pessary treatment. -Indications: Asymptomatic women, older women, those unwilling for surgery, mild degree of prolapse or in early pregnancy.

• Surgical Management: -Types (restorative, extirpative, obliterative) and choices depend on the patient's age, parity, degree and type of prolapse, and presence of prior surgery or associated conditions.

• Pessary Treatment: Used for early pregnancy, puerperium, patient unfit for surgery, and to facilitate treatment before further surgery.

Complications of Vaginal Repair

• Operative: Hemorrhage, bladder or rectum trauma.
• Postoperative: Urinary retention, sepsis.