Cephalohematoma
The short answer
Cephalohematoma is a collection of blood between a skull bone and its periosteum (the membrane covering the bone), caused by pressure during delivery. It appears as a firm, raised bump on one side of the baby's head that does not cross suture lines. It is generally harmless and resolves on its own over weeks to months. It does not affect the brain, but the breakdown of blood can contribute to jaundice.
Thousands of parents search for this exact thing. You are not alone.
By Age
What to expect by age
0-48 hours
A cephalohematoma may not be immediately obvious at birth because the bleeding accumulates slowly. It typically becomes noticeable within the first few hours to days. It presents as a firm, well-defined, raised area on one side of the head, most commonly over the parietal bone. Unlike caput succedaneum, a cephalohematoma does not cross suture lines and feels firmer. It occurs in about 1-2% of births and is more common after prolonged labor, assisted delivery (forceps or vacuum), or in larger babies. No treatment is needed in most cases.
2-7 days
The cephalohematoma may appear to grow slightly during the first few days as blood continues to accumulate, then stabilize. The bump may feel firm in the center and softer at the edges. As the blood begins to be reabsorbed, the edges may harden first, creating a crater-like feel with a soft center, which can be alarming but is normal. Doctors will monitor bilirubin levels because the breakdown of the collected blood can cause or worsen jaundice. Phototherapy may be needed if jaundice levels become elevated.
1-4 weeks
The cephalohematoma will gradually become firmer as the blood is reabsorbed and the area begins to calcify at the edges. This can make the bump feel like it has a hard rim, which is a normal part of resolution. Do not attempt to massage or press on the bump, as this will not speed healing and could cause harm. The bump should not be growing at this point. If it is getting larger, or if the skin over it becomes red or warm, contact your pediatrician.
1-3 months
Most cephalohematomas resolve completely within 2-3 months. Some may take longer, particularly larger ones. As the calcified rim remodels, the head shape returns to normal. In rare cases, a small calcified bump may persist for longer but will eventually smooth out as the skull grows. A cephalohematoma does not affect brain development or cause lasting harm. If the bump persists beyond 3 months without improvement, or if you notice any changes in your baby's head shape or development, mention it at a well-child visit.
What Should You Do?
When to take action
- A firm, well-defined bump on one side of the head that appeared within the first day or two after birth
- The bump has a hardening rim with a softer center as it begins to resolve
- The bump is gradually getting smaller over weeks
- Your baby is feeding well, alert, and developing normally despite the cephalohematoma
- You want to confirm that a bump on your baby's head is a cephalohematoma and not something else
- The bump has not started to decrease in size after 4-6 weeks
- Your baby is developing jaundice (yellow skin or eyes) that may be related to the cephalohematoma
- The bump is rapidly growing, the baby is becoming pale, or the fontanelle is bulging, as these could indicate a more serious type of bleeding (subgaleal hemorrhage) that requires emergency medical attention
- The skin over the bump becomes red, warm, or drains fluid, or the baby develops a fever, as these could indicate an infected cephalohematoma requiring urgent treatment
Sources
Related Resources
Trust your instincts. If something feels wrong, reach out to your pediatrician.
Worrying about your baby means you care. That is a good thing.
Related Medical Concerns
My Baby's Head Shape Looks Abnormal
Many babies develop temporary head shape irregularities that are completely normal. A cone-shaped head from vaginal delivery reshapes within days. Mild positional flattening (plagiocephaly) from sleeping on the back is very common and usually improves with repositioning and tummy time. However, head shape changes involving ridges, a persistently bulging fontanelle, or rapid head growth changes should be evaluated to rule out craniosynostosis.
Achondroplasia (Dwarfism) in Babies
Achondroplasia is the most common form of short-limbed dwarfism, affecting about 1 in 15,000 to 40,000 births. It is caused by a mutation in the FGFR3 gene and is usually apparent at birth with characteristic features including short limbs, a larger head, and a prominent forehead. Intelligence is normal. With monitoring for specific complications and supportive care, children with achondroplasia lead full, active, and independent lives.
Adenoid Hypertrophy and Breathing
Adenoids are lymphoid tissue located behind the nose that help fight infection in young children. When adenoids become enlarged (adenoid hypertrophy), they can block the nasal airway, causing chronic mouth breathing, snoring, nasal speech, and sleep-disordered breathing. Enlarged adenoids are most common between ages 2-7 and are a leading cause of obstructive sleep apnea in young children. Treatment ranges from watchful waiting and nasal steroids to surgical removal (adenoidectomy) if breathing or sleep is significantly affected.
How to Advocate for Your Child's Needs
You know your child better than anyone, and your observations matter. If you feel something is not right with your child's development or health, you have every right to ask questions, request evaluations, and seek second opinions. Advocating for your child is not being difficult - it is being a good parent.
Air Quality and Baby Health
Babies and young children are more vulnerable to air pollution than adults because they breathe faster, their lungs are still developing, and they spend more time close to the ground where some pollutants concentrate. The EPA recommends keeping babies indoors when the Air Quality Index (AQI) exceeds 100 (orange level). During wildfire smoke events, keep windows closed, use air purifiers with HEPA filters, and monitor your child for coughing, wheezing, or difficulty breathing. Long-term exposure to air pollution can affect lung development.
Are Allergies Linked to Neurodivergence in Children?
Research has found statistical associations between atopic conditions (eczema, food allergies, asthma) and certain neurodevelopmental differences such as ADHD and autism spectrum disorder. However, having allergies does not mean your child will be neurodivergent, and most children with allergies develop typically. These conditions may share some underlying immune and genetic pathways, but one does not cause the other.