Causes of Uterine Prolapse
Uterine prolapse is primarily caused by weakening of the pelvic floor support structures, with vaginal childbirth, advancing age, and increased body mass index being the most consistent risk factors. 1
Primary Risk Factors
- Vaginal childbirth: Multiple vaginal deliveries can cause direct or denervation injury to the pelvic floor musculature, increasing stress on the fascia and leading to weakening of the pelvic floor 2
- Advanced age: Aging contributes to progressive weakening of pelvic floor support structures 2, 1
- Menopause: Hormonal changes during menopause affect tissue integrity and elasticity 2
- Obesity: Higher BMI increases chronic intra-abdominal pressure on pelvic structures 2, 1
- Chronic straining: Activities that repeatedly increase intra-abdominal pressure contribute to prolapse development 2, 1
Pathophysiological Mechanisms
- Connective tissue abnormalities: Alterations in collagen and elastin metabolism affect tissue strength and integrity 3
- Levator ani muscle dysfunction: Damage to this key pelvic floor muscle complex compromises support 2
- Ligament disruption: Stretching or tearing of cardinal and uterosacral ligaments that normally provide uterine support 4
- Altered proteolytic balance: Changes in the activity of enzymes that degrade structural proteins and their inhibitors 3
Anatomical Considerations
- Support defects: Pelvic organ prolapse involves excessive descent of organs through the pelvic floor hiatus 2
- Compartment involvement: Prolapse may affect various compartments including anterior (cystocele/urethrocele), apical (uterine/cervical/vaginal), and posterior (rectocele) 2
- Associated conditions: Uterine prolapse often occurs with other pelvic floor disorders such as rectocele, cystocele, or enterocele 4
Epidemiological Factors
- Prevalence: Pelvic organ prolapse affects approximately 25-33% of postmenopausal women 2
- Lifetime risk: The lifetime risk of undergoing surgery for prolapse or urinary incontinence by age 80 is approximately 11% 2
- Increasing incidence with parity: Weighted prevalence rates of pelvic organ prolapse increase with parity, ranging from 1.4% to 4.5% 2
Additional Contributing Factors
- Previous pelvic surgeries: Procedures like hysterectomy may disrupt normal pelvic support 1
- Genetic predisposition: Family history may increase susceptibility to prolapse 1
- Chronic respiratory conditions: Conditions causing chronic coughing create repetitive increases in intra-abdominal pressure 2
- Occupational factors: Jobs involving heavy lifting or prolonged standing 2
Clinical Implications
- Symptom progression: Symptoms typically worsen with exertion and improve with rest 4
- Tissue damage: Severe prolapse can lead to mucosal ulcerations and bleeding from tissue exposure and friction 4
- Quality of life impact: Prolapse primarily causes morbidity affecting quality of life rather than mortality 2
Prevention Considerations
- Weight management: Maintaining healthy weight reduces pressure on pelvic structures 1
- Pelvic floor exercises: Strengthening pelvic floor muscles may help prevent progression 1
- Avoiding heavy lifting: Reducing activities that increase intra-abdominal pressure 1
- Managing constipation: Preventing chronic straining during bowel movements 1
Understanding these causative factors is essential for proper assessment and management of patients with uterine prolapse, particularly since the condition significantly impacts quality of life and often requires intervention when symptomatic.