Mother holds baby on her knees, the little head with the fontanel rests in her hands.

The fontanelles

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

What is the fontanelle?

Fontanelles (yes, there are several) are the spots on your little explorer's head where the skull bones meet. The bony plates have not fused together at birth but are lying loosely next to each other. Instead of being connected by bone, they are connected by flexible connective tissue. The fontanelles have a bit more space between the bones because more than two skull plates lie side by side there. On your baby's head, there are five bony plates and six fontanelles.

Did you know:

Not only human babies have fontanelles on their heads at birth, but also dogs, cats, and almost all other mammals. In some dog breeds, the large fontanelle remains for a lifetime.

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 on 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 that you 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 . If the fontanel bulges outward, this could be due to an infection. Please consult as soon as possible in either case.

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?

Because of the fontanelles, the passage through the birth canal is easier for your baby. 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 a bit flexible. and doctors can also feel the position of your baby at the fontanelles during birth and thus assess how the birth is progressing.

Additionally, the fontanelles are important for your baby's : 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.

Did you know:

Some doctors refer to the large fontanel at the front of the baby's head as the "window to the brain" because it allows for very easy ultrasound examinations of the brain if needed.

When do the fontanelles close?

The fontanelles of your baby are very well protected by the connective tissue above them. Nevertheless, it is important to be especially careful with the 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 opens 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: Sie wachsen bis zu ihrem ersten Geburtstag.

  • The posterior fontanelle: She closes herself off until about the 18th month of life.

But don't worry if these appointments don't quite fit your little explorer – every baby is different, and that's okay! If in doubt, your pediatrician can surely tell you if everything is okay.

Even if it doesn't look like it at first glance: your baby's fontanelles are well protected by the overlying tissue. So you don't need to worry and can enjoy the beautiful with your little explorer completely relaxed. We wish you all the best!

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