What are strictures?

I have heard of the stoma getting tighter after two to three months after gastric bypass...is that strictures? How many people usually get it and why? I had surgery seven weeks ago and have nausea from time to time but thought that was just normal. 

An esophageal stricture is a gradual narrowing of the esophagus, which can lead to swallowing difficulties. The strictures are caused by scar tissue that builds up in the esophagus.

When the lining of the esophagus is damaged, scarring develops. When scarring occurs, the lining of the esophagus becomes stiff. In time, as this scar tissue continues to build up, the esophagus begins to narrow in that area. The result then is swallowing difficulties.

One of the conditions that can lead to esophageal strictures is gastroesophageal reflux disease. Excessive acid is refluxed from the stomach up into the esophagus. This causes an inflammation in the lower part of the esophagus. Scarring will result after repeated inflammatory injury and healing, re-injury and rehealing. This scarring will produce damaged tissue in the form of a ring that narrows the opening of the esophagus.

With WLS it can be swelling also. Or the surgeons have closed it over too much. Very common occurence with us....it can be fixed with  an endoscopy procedure.