It's now three weeks i've done my umbilical hernia surgery can coughing or straining to move your bowel affect the wound?

Doubtful: I would think that normal straining at this point will not have a deleterious effect on the integrity of the wound. I would not resume more strenuous activity until directed by your surgeon.

Dr Hoepfner and another doctor agreed

Usually no: Follow your surgeon's instructions as regard to physical limitations on heavy lifting. Normal daily functions of coughing or small straining cannot be avoided. Use laxative if needed to prevent constipation.

Dr Alves agreed

It can: But not unless very vigorous. Don't exercise or do more than you have to do for another couple of mos.

Dr Hoepfner and another doctor agreed

Yes: Any maneuver that cause intra abdominal pressure put strain on the wound healing process toe the extent of dehiscence ( opening of the wound). Good luck

Dr Peltan agreed

Possible: At three weeks, your wound is beginning to get some strength. Fibroblasts are making a stronger scar. That is not to say that it is not possible to bust open your wound. It still is. Anything that increases pressure on your abdomen increase the likelihood of causing the wound to break open. Obesity can be its own risk factor. Proceed with caution.You will live the rest of your life with this belly.