When you gently stroke your little explorer's head, you can feel it: in some areas, it suddenly becomes very soft, and you can no longer feel the hard skull bone. This is your baby's so-called fontanelle. Thanks to it, birth becomes easier and more comfortable for both mother and child. It is also important for brain development. In this article, you'll learn everything about the fontanelle, its role in your baby's health, and when it closes.

What is the fontanelle?

Fontanelles (yes, there are several) are the soft spots on your little explorer's head where the skull bones meet. At birth, the bony plates have not yet fused together and lie loosely next to one another. Instead of being connected by bone, they are joined by flexible connective tissue. The fontanelles leave a bit more space between the bones because more than two skull plates meet there. Your baby's head has five bony plates and six fontanelles.

What fontanelles are there?

The six fontanelles on your little explorer's head are divided into main fontanelles and side fontanelles. The first main fontanelle is located at the front center of the head. It is diamond-shaped and already a few centimeters in size at birth. The second main fontanelle is located at the back of the head, is slightly smaller than the front one, and has a triangular shape.

The lateral fontanelles are located, as the name suggests, on the sides of the baby's head. Two of them are at the front of the head, to the right and left of the main fontanelle. There is also a lateral fontanelle at the back of the head.

What do the fontanelles look like?

The fontanelles on your baby's head are easier to feel than to see, especially if your little explorer already has a lot of hair. Depending on the light, you might be able to see the edges of the bone plates under the skin. However, it is important to watch for changes in the fontanelles. A sunken fontanel can, for example, indicate that your baby is not getting enough fluids, such as when they have diarrhea. If the fontanel bulges outward, this could be due to an infection. In either case, please consult your pediatrician as soon as possible.

If the fontanelles are slightly pulsating, or you can even see blood vessels, this is not a cause for concern. Especially when your baby is crying and therefore excited, this is completely normal, as the vessels are located directly beneath the protective tissue layer.

What are fontanelles for?

Fontanelles make it easier for your baby to pass through the birth canal. Since the skull bones have not yet fused together, they can shift against each other and even overlap during birth. This makes the little head more flexible. Midwives and doctors can also feel your baby's position at the fontanelles during birth and assess how labor is progressing.

Additionally, the fontanelles are important for your baby's brain development: in the first two years of life, the brain grows very rapidly and significantly. If the skull bones had already fused and ossified by then, this growth would not be possible.

When do the fontanelles close?

Your baby's fontanelles are very well protected by the connective tissue above them. Nevertheless, it is important to be especially careful with that delicate little head while the fontanelles are still open. They all close at different times, roughly between the third month of life and the second birthday:

• The small anterior fontanel: It closes the fastest and is usually already ossified by the third month of life.

• The large anterior fontanel: It closes in about half of all children between the sixth and 18th month of life. By the second birthday, it is closed in almost all toddlers.

• The anterior fontanelles: They close by the first birthday.

• The posterior fontanelle: It closes by about the 18th month of life.

But don't worry if these timelines don't quite match your little explorer—every baby is different, and that's okay. If you're unsure, your pediatrician can tell you whether everything is on track.

Even if it doesn't look like it at first glance, your baby's fontanelles are well protected by the tissue above them. So you don't need to worry, and you can enjoy this special time with your little explorer in a relaxed way. We wish you all the best!