If the pain persists or you develop symptoms like fever, nausea, or vomiting, reach out to ... in your belly button include: Pregnancy can cause abdominal pain as the baby grows inside the uterus ...

So for three years he collected his own belly-button lint to find out. And after interviewing ... but lint isn't the only thing inside these bizarre human crevices. Your belly button is a scar ...

One of these, Dr Baumgardt notes, is an umbilical hernia, which occurs when part of the intestine bulges through the belly button. This causes swelling or a bulge coming out of the navel.