A soft bulge of tissue or a small, localized swelling on the abdomen. Most often, a lump in the abdomen is caused by a hernia. An abdominal hernia occurs when there is an area where the muscles are weak, and this allows the internal organs to bulge through the abdominal wall. This is caused by failure of the muscular ring around the navel to close completely.
Umbilical hernias are more common in babies with a low birth weight , including premature babies.
See also gastroschisis . Incisional hernias may not appear until after straining, heavy lifting, or a prolonged period of coughing . A ureteropelvic junction obstruction may also feel like a lump in the abdomen. Seek appropriate care for chronic coughs or for constipation if you have a hernia. Straining associated with these conditions causes the intestines to protrude further into the hernia.