This topic is about managing the challenges that come with a stoma that sometimes retracts or enlarges, leading to leaks. The person experiencing this issue is looking for practical solutions to prevent leaks and handle changes in stoma size. Here are some helpful insights and advice:

1. **Convexity and Accessories**
- Many people have found success in preventing leaks from a retracting stoma by using a convex flange or wafer, or by adding convex rings. These help push the stoma outward and keep output away from the skin.
- Some products that have been helpful include the Hollister New Image two-piece system with a closed-end pouch and convex baseplate, and Eakin cohesive or colloidal rings placed under the wafer. Some people use an extra ring on the side where the abdomen dips.
- There are also convex wafers with a soft, flexible inner rim that can be adjusted to fit the stoma shape. It's a good idea to request samples from different manufacturers to find the best fit.

2. **Hydration**
- A stoma that suddenly flattens might be a sign of dehydration. Thin, watery output can undermine the wafer and cause leaks. Increasing fluid intake and monitoring urine color and output can help manage this.

3. **Obstruction Check**
- If the stoma retracts painfully, it might indicate a partial blockage. Thorough chewing, a careful diet, and seeking medical attention can help resolve this issue.

4. **Hernia Assessment**
- If a new bulge appears and pulls the stoma inward, causing leaks, it could be a small parastomal hernia. A CT scan can confirm this, and surgical repair might be necessary.

5. **Normal Movement**
- Some in-and-out movement of the stoma, known as "peek-a-boo" motion, can be normal due to peristaltic activity. If it's not painful or causing leaks, it might not need any intervention.

6. **Practical Tips**
- Using a convex wafer with a moldable or barrier ring can help maintain a seal even when the stoma retracts.
- When fitting the flange, flatten any nearby abdominal bulge upward to reduce tension.
- Order free samples of different convex systems and sizes to accommodate occasional stoma enlargement.
- Keeping a diary of hydration, output consistency, and stoma behavior can help identify patterns and triggers.