A cephalohaematoma is a hemorrhage of blood between the skull and the periosteum of any age human, including a newborn baby secondary to rupture of blood vessels crossing the periosteum. Because the swelling is subperiosteal, its boundaries are limited by the individual bones, in contrast to a caput succedaneum.

Swelling appears after 2-3 days after birth. If severe the child may develop jaundice, anemia or hypotension. In some cases it may be an indication of a linear skull fracture or be at risk of an infection leading to osteomyelitis or meningitis. The swelling of a cephalohematoma takes weeks to resolve as the blood clot is slowly absorbed from the periphery towards the centre. In time the swelling hardens (calcification) leaving a relatively softer centre so that it appears as a ‘depressed fracture’. Cephalohematoma should be distinguished from another scalp bleeding called subgaleal hemorrhage (also called subaponeurotic hemorrhage), which is blood between the scalp and skull bone (above the periosteum) and is more extensive. It is more prone to complications, especially anemia and bruising.

The usual causes of a cephalohematoma are a prolonged second stage of labor or instrumental delivery, particularly forceps delivery. Ventouse application does not increase the incidence of cephalhematoma.[citation needed] Vitamin C deficiency has been reported to possibly be associated with development of cephalhematomas.