An overview of flat head syndrome

Flat head syndrome—medically known as positional plagiocephaly—occurs when a baby’s head develops a flat spot in the first months of its life. The baby’s skull is soft, and their neck muscles are still weak during this timeframe, leading to their head resting on surfaces.

By Ashley Braun MPH RD, Medically reviewed by Lyndsey Garbi MD, Verywell Health July 08, 2021

Flat spots can occur when a baby frequently lies or sleeps in the same position, which allows the baby’s head to develop a flat spot and become misshapen. Learn more about the symptoms of flat head syndrome and how parents can help treat the condition.

Flat Head Syndrome in Babies

The number of babies developing flat head syndrome has increased over the past few decades, likely because the safest position for babies to sleep is flat on their back in their crib. Back sleeping helps to reduce the risk for sudden infant death syndrome (SIDS).^[1]

With babies spending more time sleeping on their back, they are putting light pressure on the back of their head from the bottom of the crib (or side of their head if it’s turned more to one side).

At birth, the skull is composed of multiple bones that fuse into one bone after the age of two. The skull is made of several bones, so it is soft and shapeable. This allows the head to move easier through the birth canal and allows it to expand to accommodate the brain’s rapid development.

Flat spots form when a baby spends too much time with their head laying in the same position, called positional plagiocephaly.^[2] It most often affects the back or side of the head. A flat area can even start to form in the womb if there is pressure on the skull.

Flat head syndrome won’t affect your baby’s brain development, just the shape of their head.

A rare condition called torticollis can lead to flat spots. Torticollis causes tight neck muscles that cause the head to twist to one side. This can lead your baby to hold their head in the same position frequently.

Symptoms of Flat Head Syndrome

Flat spots usually appear within the first few months of life, especially before the baby can lift their own head.

You can examine your baby’s head to see if there are any signs of flat head syndrome developing.

Examine your baby’s head from directing above to see if you notice any flattened spots on their head. If your baby has a full head of hair, it can be easier to look at their head after a bath when their hair is still wet.

Signs of flat head syndrome include: ^[2]

• Flattened spot on their head (back or sides)
• Less hair on one part of their head (this could be an early sign they are putting pressure frequently in this spot)
• One ear or one side of their forehead appears slightly pushed forward

Flat Head Syndrome: Diagnosis and Treatment

Your pediatrician will check your baby’s head shape at each wellness visit. They do this to monitor healthy growth and check for any flat spots. If you notice a flattened spot on your baby’s head, it’s best to ask your child’s healthcare provider to assess the spot.

It’s unlikely, but sometimes flat spots are a sign of a rare condition called craniosynostosis—a condition where the skull bones fuse too early.^[2]

Diagnosis is made with a simple physical exam to assess the head and neck muscles. If your child’s healthcare provider suspected craniosynostosis, they might recommend imaging to take a closer look at the skull.

Usually, flat head syndrome isn’t cause for any serious health concerns, especially when caught early. Mild to moderate flat spots may resolve through simply changing the baby’s head position regularly.

Often, flat spots improve on their own as babies start to hold their heads up, crawl, and move their own position often. You can help prevent flattened areas and encourage them to heal by: ^[2]

•  Tummy time  Supervised time spent laying on their stomach is good for your baby. When your baby is awake, you want to encourage them to spend time off their back. Tummy time helps to prevent flat spots and strengthen their neck, back, and core muscles.
•  Alternate head position  Try to alternate the direction the baby’s head is in each time you lay your baby down to sleep. Switching the direction of their head helps to rotate the pressure and prevent flat spots.
•  Hold your baby more  The more time your baby spends resting their head against flat surfaces, like a crib, car seat, or stroller, the more likely they are to develop flat spots. Alternating the arm used to hold your baby changes the side of the head the pressure is on.

If your baby tends to hold their head to one side more than the other, it could be a sign of tight neck muscles. Your healthcare provider may refer you to physical therapy to help improve the tight neck muscles. A physical therapist will suggest exercises to help to improve muscle strength and range of motion.

Helmet Therapy

Severe flat spots may require additional treatment. If flat spots don’t go away after trialing positional changes, your healthcare provider may recommend helmet therapy.^[2]

A helmet helps mold your baby’s head and prevents their head from resting on a flat surface. However, helmet therapy is only if the flat areas don’t improve from positional changes because it could lead to skin irritation or a skin rash.

Frequently Asked Questions

A Word From Verywell

Flat head syndrome improves with time, and most babies outgrow their flat spots. The flattened areas won’t affect your baby’s brain development.

If their neck muscles are tight, working with a physical therapy can help improve the range of motion in those muscles.

When your baby is awake, have them spend time off the back of their head. Tummy time and moving their head position may help prevent flat spots.

Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.

Source Verywell Health

References

1. Safe Infant Sleep Interventions: What is the Evidence for Successful Behavior Change? Moon RY, Hauck FR, Colson ER. Curr Pediatr Rev. 2016;12(1):67-75. doi: 10.2174/1573396311666151026110148. Full text
2. Flat head syndrome. Kids Health from Nemours. Updated September 2019.
3. Prevalence and characteristics of positional plagiocephaly in healthy full-term infants at 8-12 weeks of life, Ballardini E, Sisti M, Basaglia N, Benedetto M, Baldan A, Borgna-Pignatti C, Garani G. Eur J Pediatr. 2018 Oct;177(10):1547-1554. doi: 10.1007/s00431-018-3212-0. Epub 2018 Jul 20.

Also see
What to Know About a Baby’s Misshapen Head Verywell Health
Changes to a Baby’s Head Shape: When to Worry Verywell Health
An Overview of Skull Birth Defects: Anencephaly, Craniosynostosis, and Encephalocele Verywell Health
Flat Head Syndrome (Plagiocephaly) in Babies What to Expect