Rectal prolapse and constipation

At a glance

Rectal prolapse and constipation have a complex, bidirectional relationship. Constipation (and the straining it causes) is a risk factor for developing prolapse. But prolapse itself can cause or worsen constipation by creating a physical obstruction. Each condition feeds the other, creating a cycle that can be difficult to break.

This guide explains how the two conditions interact and what can be done to manage both.

The two-way relationship

Constipation leading to prolapse

Chronic constipation means chronic straining. Straining creates sustained downward pressure on the pelvic floor and the supports that hold the rectum in place. Over time, this can:

• Weaken the ligaments that anchor the rectum
• Stretch the pelvic floor muscles
• Allow the rectum to descend or fold inward

This does not happen overnight. It is a gradual process, often over years, that eventually results in prolapse.

Prolapse leading to constipation

Once some degree of prolapse is present, it can obstruct normal evacuation:

• Internal prolapse: the rectum folds into itself, creating a blockage that stool must push through. People describe difficulty emptying, a sense of blockage, and the need to strain harder.
• External prolapse: the protruding tissue can interfere with normal bowel function and may need to be reduced (pushed back) before evacuation can proceed.

The result: more straining, which worsens the prolapse, which worsens the constipation. The cycle tightens.

Breaking the cycle

Address the constipation

This is the most controllable aspect and the starting point for most management plans:

• Adequate fibre: enough to produce soft, easy-to-pass stools
• Adequate hydration: two to three litres daily
• Avoid straining: go when the urge comes, do not force, limit toilet time
• Stool softeners: if dietary measures are insufficient
• Good toilet posture: feet elevated, leaning forward

Support the pelvic floor

• Pelvic floor exercises: under guidance from a specialist physiotherapist
• Biofeedback: learning to coordinate pelvic floor muscles during defecation
• Avoiding heavy lifting: which increases intra-abdominal pressure

Consider the prolapse

If constipation management and pelvic floor rehabilitation are not sufficient, the prolapse itself may need to be addressed:

• Assessment: detailed examination and potentially imaging (defecating proctogram) to characterise the prolapse
• Conservative management: for mild prolapse, the measures above may be sufficient
• Surgical options: for significant prolapse that is not responding to conservative approaches

The role of investigation

Understanding the relationship between constipation and prolapse in your specific case often requires investigation:

• Defecating proctogram: shows how the rectum behaves during straining — identifies internal prolapse, rectocele, or other structural issues
• Anorectal physiology: measures pressures and function
• Transit studies: assess how quickly material moves through the bowel — identifies slow transit constipation

These investigations help your care team understand whether the constipation is driving the prolapse, the prolapse is driving the constipation, or both — and tailor the management plan accordingly.

The honest picture

The chicken-and-egg nature of this relationship means there is rarely a single, simple fix. Effective management usually involves:

1. Optimising stool consistency (reduce straining)
2. Strengthening the pelvic floor (provide better support)
3. Addressing the prolapse if conservative measures are insufficient (correct the structure)

This is a process, not a quick resolution. But understanding how the two conditions interact is the first step toward breaking the cycle.