Vaginal (Pelvic Organ) Prolapse

Introduction

Pelvic organ prolapse is the descent of one or more of the pelvic organs - the bladder, uterus or cervix, or bowel - into or through the vagina, resulting from weakness or damage to the muscles, ligaments and connective tissue (the levator ani and endopelvic fascia) that normally support them.¹

It is extremely common, particularly in parous and postmenopausal women, though the correlation between anatomical findings on examination and bothersome symptoms is imperfect - many women with mild prolapse on examination are asymptomatic, while others with modest descent report significant impact on quality of life. Management is therefore guided as much by symptoms as by examination findings.

Classification by compartment

Prolapse is classified by which vaginal compartment is affected, since this determines the likely associated symptoms and the specific surgical approach if needed. More than one compartment is often involved simultaneously.¹

Procidentia describes complete uterine prolapse, where the uterus and cervix protrude entirely outside the introitus - the most severe form of apical prolapse.

Risk factors

• Vaginal delivery: the strongest modifiable risk factor, particularly with instrumental delivery, a prolonged second stage, or a large baby
• Advancing age and postmenopausal status (loss of the collagen-supportive effect of oestrogen)
• Obesity
• Chronic raised intra-abdominal pressure: chronic cough, chronic constipation with straining, heavy lifting
• Connective tissue disorders (e.g. Ehlers-Danlos syndrome)
• Previous pelvic surgery, including hysterectomy
• Family history

Clinical features

The hallmark symptom is a sensation of a lump, bulge or dragging/heaviness in the vagina, characteristically worse with standing, straining or by the end of the day, and improved by lying down.² Additional symptoms often point to the compartment involved.

Dyspareunia and impact on sexual function are common across all types. Examination is performed with the woman straining, and ideally standing if symptoms are not reproduced supine, using a Sims speculum to assess the anterior and posterior walls separately and identify the leading edge and compartment(s) involved.

Staging: the POP-Q system

The Pelvic Organ Prolapse Quantification (POP-Q) system is the standardised method for describing prolapse severity, measuring the position of defined points relative to the hymen (the fixed reference point) in centimetres.³

In practice, many clinicians use a simpler descriptive grading (mild, moderate, severe, or 'prolapse to/beyond the introitus') for day-to-day communication, but POP-Q is the standard for research and specialist documentation.

Investigations

Prolapse is diagnosed clinically on examination. Additional tests are directed at associated symptoms or before planning intervention:

• Urinalysis - if urinary symptoms are prominent, to exclude infection
• Post-void residual bladder volume - if voiding difficulty is reported
• Urodynamic studies - if surgery is planned and occult stress incontinence needs to be assessed (prolapse can mask underlying stress incontinence by kinking the urethra)
• Renal ultrasound - rarely needed, considered in severe prolapse with a risk of ureteric obstruction

Management

Management is guided by symptom severity, the woman's preferences, fitness for surgery, and whether future pregnancy is desired, rather than by POP-Q stage alone.²

Conservative management

• Pelvic floor muscle training (PFMT): first-line for mild-to-moderate prolapse, typically supervised by a specialist physiotherapist for at least 16 weeks
• Weight loss and management of chronic cough/constipation to reduce intra-abdominal pressure
• Vaginal pessaries: mechanical devices (most commonly a ring or shelf pessary) inserted to support the prolapsed organs; suitable for women who want to avoid or delay surgery, are not fit for surgery, or wish to preserve fertility; require review and changing periodically (e.g. every 4-6 months)
• Topical vaginal oestrogen: improves vaginal tissue quality and comfort in postmenopausal women, used alongside pessary or surgical management, and can reduce pessary-related complications such as erosion

Surgical management

Reserved for women with bothersome symptoms who have not responded to, or do not want, conservative measures, and who have completed their family (as vaginal delivery after prolapse surgery risks recurrence). The procedure is chosen according to the compartment(s) involved.¹

Complications

• Recurrent urinary tract infections from incomplete bladder emptying
• Urinary retention in severe anterior/apical prolapse
• Ulceration or excoriation of prolapsed tissue exposed outside the introitus
• Obstructed defecation from significant rectocele
• Sexual dysfunction
• Recurrence after surgical repair, particularly with ongoing risk factors (obesity, chronic cough)

Prognosis

Most women achieve good symptom control with conservative measures (pelvic floor training, pessary) or surgery, though prolapse - especially apical and multi-compartment prolapse - has a recognised risk of recurrence over time, particularly if predisposing risk factors persist. Addressing modifiable risk factors (weight, chronic cough, constipation) alongside definitive treatment improves durability of results.