From what I have googled it's caused when the small intestines are not formed properly, but like I said I don't know much as I have not seen the doctor to get all the information
The opening leading out of the stomach into the duodenum of the small intestine is abnormally narrowed making it difficult for food to pass. Two most common signs are projectile vomiting and failure to thrive due to lack of food. More common in boys. Surgery opens up that passageway and has a very high success rate.
It's very good they caught this so they can take measures to correct right away. Some babies are born and it isn't known there is a problem until the baby starts having severe problems. Think good thoughts mama and pray about it. They thought my son had cancer at birth. He had a rare tumor on his cheek near his right ear that was removed at 3 weeks. No problems since. I know how you feel being scared. Just try to stay positive.
We are doing our best to keep positive, I am trying not to stress myself out because that's not good for me or baby. We are just taking it one day at a time meeting with everyone we need to and getting the plan in place