Can an abdominal hernia cause internal bleeding?

Not directly: The most common type of hernia (in the groin) would not cause intestinal bleeding unless the intestine were strangled in the hernia -- and this would cause many more problems than simple bleeding. Hiatal herniae can facilitate acid refluxing into the esophagus which may lead to ulcers or erosions which may case esophageal bleeding, but not usually intestinal. Why do you ask?