A cephalohematoma is an accumulation of blood under the scalp. During the birth process, small blood vessels on the head of the fetus are broken as a result of minor trauma. Specific to a cephalohematoma, small blood vessels crossing the periosteum are ruptured and serosanguineous or bloody fluid collects between the skull and the periosteum. The periosteum is the membrane that covers the outer surface of all bones. The bleeding is gradual; therefore, a cephalohematoma is not evident at birth. A cephalohematoma develops during the hours or days following birth. Because the fluid collection is between the periosteum and the skull, the boundaries of a cephalohematoma are defined by the underlying bone. In other words, a cephalohematoma is confined to the area on top of one of the cranial bones and does not cross the midline or the suture lines. Because the collection of blood is sitting on top of the skull and not under it, there is no pressure placed on the brain.
The cause of a cephalohematoma is rupture of blood vessels crossing the periosteum due to the pressure on the fetal head during birth. During the process of birth, pressure on the skull or the use of forceps or a vacuum extractor rupture these capillaries resulting in a collection of serosanguineous or bloody fluid. Factors that increase pressure on the fetal head and the risk of the neonate developing a cephalhematoma include:
These factors contribute to the traumatic impact of the birthing process on the fetal head.
Cephalohematoma is a subperiosteal accumulation of blood that occurs with an incidence of 0.4% to 2.5% of all live births. They are more common in primigravidae, large infants, infants in an occipital posterior or transverse occipital position at the start of labor, and following instrument-assisted deliveries with forceps or a vacuum extractor. For unknown reasons, cephalohematomas occur more often in male than in female infants.
Cephalohematoma is a minor condition that occurs during the birth process. Pressure on the fetal head ruptures small blood vessels as when the head is compressed against the maternal pelvis during labor or pressure from forceps or a vacuum extractor used to assist the birth. Shearing action between the periosteum and the bone causes bleeding of the emissary and diploic veins. As blood accumulates, the periosteum lifts away from the skull. As the bleeding continues and fills the subperiosteal space, pressure builds, and the accumulated blood acts as a tamponade to stop further bleeding.
A comprehensive history of the labor and birth is needed to identify newborns at risk of developing a cephalohematoma. Factors that increase pressure on the fetal head and the risk of developing a cephalhematoma include:
Because of the slow nature of subperiosteal bleeding, cephalohematomas usually are not present at birth but develop hours or even days after birth. Therefore, repeated inspection and palpation of the newborn’s head is necessary to identify the presence of a cephalohematoma. Ongoing assessment to document the appearance of a cephalohematoma is important. Once a cephalohematoma is present, assessing and documenting changes in size is continued. The most obvious sign of a cephalohematoma is a soft, raised area on the newborn’s head. A firm, enlarged unilateral or bilateral bulge on top of one or more bones below the scalp characterizes a cephalohematoma. The raised area cannot be transilluminated, and the overlying skin is usually not discolored or injured. Cranial sutures define the boundaries of the cephalohematoma. The parietal bones are the most common site of injury, but a cephalohematoma can occur over any of the cranial bones.
There is no diagnostic test for a cephalohematoma. Diagnosis is based on the characteristic bulge on the newborns head. However, some providers may request additional tests, including x-rays, CT scan, or ultrasound to evaluate for potential fractures of the skull or other problems below the skull, which could impact the newborn’s brain. Additional testing is especially warranted if the newborn's behavior changes or other problems, such as respiratory, cardiovascular, or neurological are present.
Treatment and management of a cephalohematoma are primarily observational. The mass from a cephalohematoma takes weeks to resolve as the clotted blood is slowly absorbed. Over time, the bulge may feel harder as the collected blood calcifies. The blood then starts to be reabsorbed. Sometimes the center of the bulge begins to disappear before the edges do, giving a crater-like appearance. This is the expected course for the cephalohematoma during resolution.
One should not attempt to aspirate or drain the cephalohematoma. Aspiration is not effective because the blood has clotted. Also, entering the cephalohematoma with a needle increases the risk of infection and abscess formation. The best treatment is to leave the area alone and give the body time to reabsorb the collected fluid.
Usually, cephalohematomas do not present any problem to a newborn. The exception is an increased risk of neonatal jaundice in the first days after birth. Therefore, the newborn needs to be carefully assessed for a yellowish discoloration of the skin, sclera, or mucous membranes. Noninvasive measurements with a transcutaneous bilirubin meter can be used to screen the infant. A serum bilirubin level should be obtained if the newborn exhibits signs of jaundice.
Newborns with a cephalohematoma and no other problems are usually sent home with their parent or parents. Parents need to observe the bulge on the newborn's head for any changes, including an increase in size during the first week following birth. Parents also need to monitor for any behavioral changes such as increased sleepiness, increased crying, change in the type of cry, refusal to eat, and other signs that the infant might be in pain or having a problem. Recovery from a cephalohematoma requires little action except for ongoing observation. While seeing a bulge on a newborns head can be concerning, a cephalohematoma is rarely dangerous and resolves with no lasting consequences.