Learn all about fontanelles, the soft spots on your newborn’s head.

Many parents are afraid to touch fontanelles, the soft spots on their newborn’s head. Why are they there? Should you avoid touching them?

What are fontanelles?

When a baby is born, the bones in their head are not yet fully fused. This is why you can feel soft spaces in their skull. These are known as fontanelles. They are spaces between the bones. They aren’t holes because the bones are connected by tissue. There are two fontanelles:

  • The large fontanelle located on top of the newborn’s head, near the front. It is diamond-shaped and measures approximately 3–6 cm in width.
  • The small fontanelle located at the back of the head. It looks like a small triangle and is about 1 cm wide.

Why are they there?

The fontanelles mainly facilitate the passage of the baby during delivery. Because these areas are softer, they allow the head to deform a bit so the baby can get out more easily. Don’t worry, this doesn’t damage the brain, and the head will gradually return to its original shape. This may take a few hours, a few days, or even a few weeks.

After birth, the fontanelles allow your baby’s brain to develop properly. The brain grows rapidly during the first two years. In the first year alone, a baby’s brain doubles in size.

Should I avoid touching my baby’s fontanelles?

The fontanelles are delicate, but it’s okay to touch them. The important thing is to do so gently. When washing your baby’s hair, for example, you should avoid putting too much pressure on these soft areas, but you can stroke their head without any problem. The fontanelles are made of tissue that protects the brain.

My baby’s large fontanelle seems to bulge a bit. Is this normal?

Yes, that’s perfectly normal. The fontanelles are flexible, so they move along with the air in the lungs. That’s why the large fontanelle bulges a little when your baby coughs or cries. Even when your baby is calm, you can see or feel their large fontanelle move to the rhythm of their heartbeat.

Preventing flat head
Because your baby’s skull bones are still soft, they can change shape and become flat if your little one’s head is always resting on the same side. Here are a few tips to prevent this:
  • Place your baby in a variety of positions when they’re awake to reduce their risk of developing a flat head.
  • Don’t always leave them in their car seat or baby seat. Place them on their tummy from time to time and use a baby carrier to carry them against your body.
  • When you put your baby to bed, make sure their head isn’t always turned to the same side. You can do this by alternating the position in which you put them to bed: their head at the foot on the bed one night, the next day, the reverse.

Why do doctors examine the fontanelles?

During the first two years, the doctor will examine your baby’s head during your medical checkups to make sure that the fontanelles are closing normally.

They will also measure your baby’s head to make sure their brain is growing as expected. Examining the fontanelles can also help the doctor detect certain health problems.

If the baby’s fontanelles are depressed and hollow, it may be a sign of dehydration. If the fontanelles are larger and very prominent, this can be a sign of certain diseases. However, these cases are very rare. In addition, keep in mind that a big head doesn’t mean that something’s wrong.

At what age do the fontanelles close?

Over time, the bones of the skull join and fuse together. The small fontanelle at the back of the baby’s head closes first, at around the age of 2 months. The large fontanelle, located at the front of the head, takes longer. It closes gradually between the ages of 9 months and 2 years.

Things to keep in mind

  • Fontanelles are soft spaces on a baby’s head that disappear when the skull bones join together.
  • You can gently touch your baby’s fontanelles.
  • It’s normal for the fontanelle at the front of the head to swell a little when your baby cries.


Naître et grandir

Scientific review: Dr. Jean-Philippe Blais, family physician specializing in perinatal care
Research and writing: The Naître et grandir team
March 2018


Photo: GettyImages/GrapeImages