Dr. Greene's Answer
A cephalohematoma is a collection of blood under the scalp that usually comes from birth trauma. It’s more common after a vacuum is used for delivery but can happen with any delivery. A cephalohematoma may be associated with an underlying skull fracture in about 5-10% of cases. It may also contribute to hyperbilirubinemia (jaundice) in the newborn.
A cephalohematoma often takes many months to go away and gets quite firm before it does.
As it goes away, usually the middle disappears first, followed by the edges, which can get quite hard before being absorbed into the body. The remaining bump can feel a bit like a crater before it completely disappears