When does the baby soft spot (Fontanelle) close?

Zariah Kale

Zariah Kale

Zariah is a writer, history nerd, amateur chef and mum of three. When she is not negotiating screen time with one of her two tweens, or falling asleep during movies, you'll find her scouring vintage shops for one-of-a-kind pieces or apologising to friends for the "late reply" over text.
Updated on Jun 14, 2024 · 5 mins read
When does the baby soft spot (Fontanelle) close?

My husband and I once laughed about the variety of warnings that covered every baby product that we had purchased. From the serious ones that warned of ‘choking hazards’ to some of the overly dramatic ones to ones that apparently assumed that parents of a newborn were just plain stupid.

“Don’t touch when hot.” 

Or “This is not a toy” – on a breast pump!

Then we brought our newborn home.

Let’s just say there are people who don’t have babies and parents who have just been handed the tiniest, most delicate creatures with ten tiny fingers and ten tiny toes.

Suddenly, all those warnings made so much sense! You question safety at every turn.

Our offspring was so delicate that half the time we were worried we might accidentally hurt her just by holding her. Then another parent casually mentioned something about a soft spot.

What? Do they actually have a soft spot in their skull? What is it? And what if you accidentally pushed it mid-bath?

Well, we had questions! And if you are a new parent, you may have the same concerns. So here’s all you need to know about newborn fontanelles:

When should I be concerned about my baby’s fontanelle?

The fontanelle, also known as the soft spot, is the area on a baby’s head where the skull bones have not yet fused. Fontanelles are normal in babies and typically close as the baby grows older.

However, there are times when you should be concerned about your baby’s head.

Here are some examples:

Sunken fontanelle:

If it appears sunken, it may indicate dehydration.

This is especially concerning if your baby also exhibits irritability, a dry mouth, decreased urine output, or lethargy. Dehydration can be fatal in infants, so seek medical attention if you notice these symptoms.

Fontanelle bulging:

A bulging fontanelle can indicate increased pressure inside the baby’s skull. This pressure may be caused by a variety of conditions. These include meningitis, encephalitis, and hydrocephalus. If you notice a bulging fontanelle as well as symptoms such as high fever, excessive crying, vomiting, seizures, or behavioural changes, seek immediate medical attention.

Fontanelle that remains open for an extended period of time:

Fontanelles usually close between the ages of 18 and 24 months. If your baby’s fontanelle remains open after this age, this is cause for concern. An open fontanelle in an older child could indicate a developmental issue or an underlying medical condition. Consult your paediatrician to determine the cause and the best course of action.

Changes in fontanelle size or shape

If you notice any sudden changes in the size or shape of your baby’s fontanelle, you should have it evaluated by a healthcare professional. It could indicate a problem with the normal growth and development of the skull bones.

How do you know if your fontanelle is normal?

To determine if your baby’s fontanelle is normal, you need to observe its appearance as well as monitor your baby’s overall health.

A normal fontanelle should be soft to the touch, with a slight indentation or dip, rather than hard, bulging, or excessively sunken. Its surface should be flat and even, with no unusual lumps or bumps. Fontanelles vary in size and shape between babies, with the anterior fontanelle being larger and closing later than the posterior fontanelle

The anterior fontanelle for most babies closes between 12 and 18 months of age, while the posterior fontanelle closes earlier, around 2 to 3 months. If your baby’s fontanelle exhibits these characteristics and he or she is healthy, meeting developmental milestones, and not experiencing any concerning symptoms, the fontanelle is most likely normal.

However, remember that you should always consult your paediatrician at regular check-ups or if you have specific concerns. They can provide a professional assessment based on their expertise and knowledge of your baby’s medical history.

What if I accidentally pushed my baby’s soft spot?

Accidentally pushing or touching your baby’s soft spot (fontanelle) is a common concern among parents.

The fontanelle is a relatively resilient structure designed to protect your baby’s developing brain. However, it’s natural to be concerned if you accidentally apply pressure to that area. Here’s what you should do if you find yourself in this situation:

Keep calm and don’t freak out

Panicking will not help you or your baby, so take a deep breath and try to remain calm. Remember that the fontanelle is naturally protected by a layer of tough tissue, so minor accidental pressure is unlikely to cause harm.

Evaluate your baby’s reaction

Now that you are calm, your mind can focus on deciding what to do next.

First, observe your baby for any signs of distress or discomfort. If your baby starts crying or appears to be in pain, contact your paediatrician or seek medical attention right away.

Keep an eye out for any unusual symptoms

Keep an eye on your baby in the hours and days following the incident for any unusual symptoms that could indicate a problem. Look for signs such as persistent crying, vomiting, behavioural changes, excessive sleepiness, or swelling in the fontanelle area. If you notice any concerning symptoms, it is best to consult a healthcare professional.

Seek medical attention

So your baby is doing fine, but you have an uneasy feeling. In that case, always, always go with your gut. If you are still concerned, even though your baby is happy and not exhibiting any concerning symptoms, it is always best to err on the side of caution and seek medical advice.

Contact your paediatrician or a healthcare professional for advice and an appropriate evaluation.

At what age does the Fontanelle close?

The closure of the fontanelles varies from baby to baby, but here are some general timelines:

Anterior fontanelle: 12-18 months

The anterior fontanelle is the larger of the two fontanelles, located at the top of the head. It is typically diamond-shaped and takes longer to close. The anterior fontanelle typically closes between the ages of 12 and 18 months. However, some babies’ anterior fontanelles may close as early as nine months or as late as 24 months.

Posterior fontanelle: 2-3 months

The posterior fontanelle is smaller and located at the back of the head. It has a triangular or irregular shape. The posterior fontanelle closes earlier than the anterior fontanelle, usually around 2 to 3 months of age. The skull bones at the back of the head have typically fused by this time.

And there you have it. All you need to know about newborns and newborn fontanelles.

Related Articles

What to do when the dreaded Gastro strikes…
A parents guide to gastro: Here’s what you need to know
What to do when your little one has Gastro

Related Articles

Loved this article?

Share with a friend

Hey parents!


Get paid to review the latest brands and products

Join Now - it’s FREE