This article is for general information only and does not replace medical advice. If in doubt, contact your paediatrician or midwife.
Flat Head Syndrome (Plagiocephaly) in Babies
Plagiocephaly (flat back of head or asymmetric head shape) affects nearly half of all babies in the first months. In most cases, it is a positional deformity that resolves with simple measures like tummy time and repositioning. Rarely, craniosynostosis (premature suture closure) is the cause, which requires medical evaluation.
Possible Causes
- 1Back sleeping — lifesaving (SIDS prevention), but common cause of flattening
- 2Preferred head position to one side (positional preference/torticollis)
- 3Too little tummy time while awake
- 4Too much time in car seat, bouncer, or carrier (hard, flat surface)
- 5Prematurity (softer skull bones)
- 6Very rarely: craniosynostosis (premature closure of a skull suture)
What You Can Do
- Regular tummy time while awake — possible from day 1, gradually increase several times daily
- Regularly change head position during sleep (alternately to left and right)
- Offer stimulation from the non-preferred side (toys, talking, light)
- For torticollis: physiotherapy with targeted stretching exercises
- Helmet therapy (cranial orthosis) only for severe deformity from 4-6 months — medical recommendation needed
When to See a Doctor
- Head shape does not improve despite consistent repositioning (after 2 months)
- Palpable ridges or bumps along skull sutures
- Head circumference not following growth curve
- Fontanelle closes notably early (before 6 months)
- Asymmetry getting worse instead of better
- Baby cannot turn head to the other side at all (fixed torticollis)
Age-Specific Notes
Most positional head deformities develop between months 1 and 4 and resolve on their own by 12-18 months as the baby sits, crawls, and lies less on the back of the head. Helmet therapy (if needed) is most effective between 4 and 8 months when skull bones are still mouldable. After 12 months, helmet therapy is usually no longer effective.
Frequently Asked Questions
Should my baby sleep on their stomach to fix the head shape?
Does my baby need a helmet?
Can an asymmetric head harm my baby?
Weekly tips for you
Personalised info for your stage — free, no spam.
Question about Flat Head Syndrome (Plagiocephaly) in Babies?
Our AI answers instantly — with empathy and evidence.
This article is for general information only. It does not replace individual medical advice. If you have concerns, contact your paediatrician, midwife, or call emergency services.