An adhesion is scar tissue that forms a connection between tissues or organs that are not normally connected.
For example, after abdominal surgery, adhesions can form between the intestines, uterus, fallopian tubes, ovaries, bladder, and other organs. The scar tissue may tighten around the bowel, and either partially or completely close it off. This may cause bowel obstruction. If this happens, food that is being digested can't move past the obstruction. This can cause expansion of the bowel, vomiting, and severe abdominal or pelvic pain.
Significant adhesions may be present and cause no serious problems. But sometimes, just a small adhesion can cause a lot of pain or even a bowel obstruction.
Treatment depends on where the adhesions are and what kinds of problems they cause.