Why Is The Back Of My Head Flat Causes And What To Do

A flat spot at the back of the head can be concerning, especially for new parents or adults who notice changes in their skull shape over time. While it may look unusual, a flattened occipital area — the back of the skull — is often harmless and commonly caused by positional factors rather than serious medical conditions. Understanding the root causes and knowing when to take action can help ease anxiety and guide effective solutions.

Understanding Positional Plagiocephaly

The most frequent cause of a flat head, particularly in infants, is positional plagiocephaly. This condition occurs when constant pressure on one part of the skull leads to flattening. Babies’ skulls are soft and malleable during the first few months of life, making them susceptible to external forces.

Sleeping position plays a major role. Infants who spend prolonged periods lying on their backs — especially in cribs, car seats, or bouncers — can develop flat spots where the head consistently rests. While back sleeping is recommended to reduce the risk of SIDS (Sudden Infant Death Syndrome), lack of variation in head positioning increases the chance of deformation.

Tip: Change your baby’s head position each night — turn it slightly to the left one night, right the next — to distribute pressure evenly.

Anatomical and Developmental Factors

Beyond positioning, some babies are born with or develop skull asymmetries due to in-utero positioning or birth trauma. For example, a cramped womb in multiple pregnancies or prolonged labor can lead to molding of the skull. These cases may resolve naturally within weeks as the infant begins moving more freely.

In rare instances, craniosynostosis — the premature fusion of skull sutures — can mimic flat head syndrome but requires urgent medical evaluation. Unlike positional flattening, craniosynostosis restricts brain growth and often results in an abnormally shaped head, bulging fontanelle, or developmental delays.

“Most cases of flat head are cosmetic and improve with repositioning and tummy time. True craniosynostosis affects less than 1 in 2,000 births and needs surgical correction.” — Dr. Lena Patel, Pediatric Neurologist

What About Adults? Can You Develop a Flat Head Later?

While less common, adults may also notice a flatter appearance at the back of the head. This can result from long-term habits such as:

• Consistently sleeping in the same position (especially supine with little head movement)
• Prolonged sitting with the head resting against a chair
• Postural imbalances affecting neck and spine alignment
• Natural aging and bone remodeling over decades

In some cases, individuals report noticing the flatness only after cutting their hair short or being told by someone else. Unless accompanied by pain, neurological symptoms, or recent trauma, adult-onset flatness is typically benign and related to soft tissue padding or habitual pressure.

When to Seek Medical Advice

Not every flat head requires intervention, but certain red flags warrant professional assessment:

Symptom	May Be Normal	See a Doctor
Mild flattening with symmetrical features	✓ Yes
Noticeable asymmetry in face or forehead		✓ Yes
Bulging or sunken soft spot (in infants)		✓ Yes
Developmental delays or irritability		✓ Yes
New flattening in adulthood with headaches		✓ Yes

Practical Steps to Prevent and Correct a Flat Head

For infants, early intervention yields the best outcomes. The skull becomes less moldable after 6 months, so acting quickly is key. Here’s a step-by-step approach:

1. Maximize supervised tummy time: Start with 3–5 minutes several times a day, increasing gradually. This strengthens neck muscles and reduces pressure on the back of the head.
2. Vary head position during sleep: Alternate the direction your baby faces each night. Use environmental cues like placing toys or lights on different sides of the room to encourage turning.
3. Limits time in containers: Reduce use of car seats, swings, and bouncers when not traveling. Prolonged containment increases pressure on the skull.
4. Holding and carrying: Hold your baby upright frequently throughout the day. Carriers and slings help keep the head off flat surfaces.
5. Check for torticollis: If your baby consistently tilts their head to one side or resists turning, consult a pediatrician. Physical therapy can correct tight neck muscles contributing to flat spots.

Tip: Rotate your baby’s crib placement weekly. Changing the wall they face encourages them to turn their head in different directions to see the room.

Helmet Therapy: When Is It Necessary?

For moderate to severe cases that don’t improve by 5–6 months, doctors may recommend a cranial remolding helmet. These custom-fitted devices gently guide skull growth into a more symmetrical shape.

Helmets are typically worn 23 hours a day for 3–6 months and work best when started between 4 and 12 months of age. While effective, they are not always needed. Studies show that repositioning techniques alone resolve about 77% of mild to moderate cases.

Real-Life Example: Emma’s Experience with Her Son

Emma, a first-time mother from Portland, noticed her 3-month-old son had a flattened area on the right side of his head. He preferred looking to the left and would cry when she tried to reposition him during sleep.

After consulting her pediatrician, she learned he had mild torticollis. She began daily stretching exercises under the guidance of a physical therapist and increased tummy time. By 6 months, the flat spot had significantly improved without needing a helmet. “It was stressful at first,” she said, “but consistency made all the difference.”

Prevention Checklist for Parents

Use this checklist to reduce the risk of developing a flat head in infants:

• ✅ Practice tummy time 3–5 times daily
• ✅ Alternate your baby’s head position while sleeping
• ✅ Limit time in car seats and carriers outside of travel
• ✅ Encourage visual tracking with toys on both sides
• ✅ Hold your baby upright often during awake periods
• ✅ Monitor for signs of torticollis (head tilt, limited motion)
• ✅ Schedule regular well-baby checkups to track development

Frequently Asked Questions

Can a flat head affect brain development?

No, positional plagiocephaly does not impact brain growth or cognitive function. The brain continues to develop normally even with skull asymmetry. However, underlying conditions like craniosynostosis can affect brain development and require prompt treatment.

Will my child always have a flat head?

In most cases, the flattening improves dramatically over time. As babies begin to sit up, crawl, and walk, pressure on the back of the head decreases. Hair also grows in, making residual flatness less noticeable. By school age, many children show no visible signs.

Do helmets work for older babies?

Helmets are most effective between 4 and 12 months when the skull is still rapidly growing. After 14 months, the bones harden, and reshaping becomes less efficient. Some improvements can still occur, but outcomes are less predictable in older infants.

Final Thoughts and Next Steps

A flat spot at the back of the head is usually a temporary, manageable condition — especially when addressed early. Whether you’re a concerned parent or an adult noticing subtle changes in skull contour, understanding the causes empowers you to take informed steps.

For infants, simple daily adjustments in positioning and activity can make a significant difference. For adults, reassurance and posture awareness are often sufficient. But never hesitate to consult a healthcare provider if you observe asymmetry, developmental concerns, or sudden changes.

💬 Have questions about your child’s head shape or experiences with flat head correction? Share your story in the comments — your insights could help another parent feel less alone.