A prolapse (and I am assuming that your are taking about a bowl/rectum prolapse and not a hemi-penis one) can be caused by several different problems.
A bacterial infection can weaken the muscles used to prevent it.
Too small of a cage can prevent the snake from getting enough exercise to make the muscles strong enough.
Too often or too large of feedings can produce too frequent of bowl movements causing the snake to prolapse.
Dehydration can cause the snake to be constipated and push too hard and prolapse.
Too cold of a cage will cause digestion to be too slow, causing the food to partially rot and cause a prolapse.
Most of the prolapse problems can be treated, either with medication or husbandry changes. either way I would not feed the snake for 3 weeks or so after the repair and then when you do start back up start with very small meals every 10 days. Make sure your snake is defecating before you feed him again. The small meals should continue for six months or so, slowly getting to the normal prey size. If the snake is an adult then breeding will have to be put aside for the season and let her heal. Snakes heal very slowly and need lots of time due to their slower metabolism, so if you try to rush the recovery the chance a another prolapse is greatly increased.
Another thing that you should have the vet do is check the stool for bacteria and parasites, ridding this from your snake (if it was the cause) is a must to prevent it from happening again.
Good luck
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Jim Hopkins "Hoppy"
Hopkins Holesale Herps
Hopfam1@aol.com