Fontanel in newborns - what you should know

In nature, everything is rational, and it created man as he is, not by chance. So, a child is born still not at all strong and needs a careful attitude and care. And precisely because of this, he is able to be born unscathed: the suppleness of his small body, and especially the shape of his tiny head, provides the most comfortable movement along the birth canal.

In this natural process, the baby is helped by special formations on the head - the so-called fontanelles. What are they and why were they intended by mother nature?

Definition

The fontanel in a newborn is a non-ossified area of ​​the cranial vault connecting its bones. Unlike an adult, in which the head is a single structure, in infants the bones are fenced off from each other and connected by movable sutures, and fontanels are formed at their joints. In their area, the baby's brain is covered only by its shells themselves, by a membrane from connective tissue and directly by the skin.

They got their name due to their similarity to the source of water that erupts from the bowels of the earth: similarly, this island of life in a child is a connection with the outside world, through it the baby can report possible problems and concerns.

Varieties of fontanel

A newly born baby, as a rule, has six non-ossified zones.

What and where is the fontanel in the newborn?

• The front, or large, is at the junction of the parietal and frontal bones of the skull, about 2 cm in size.
• The posterior, or small, fontanel in a newborn is found at the junction of the parietal and occipital bones, approximately 1.5 cm in size.
• Lateral: a pair of wedge-shaped and a pair of mastoid. They are located on both sides of the head between the temporal, frontal, sphenoid and parietal bones.

What is their importance?

Thanks to fontanelles in newborns, the bones of the brain are mobile, which is very important during childbirth. When the baby is ready to be born, in the process of opening the cervix, the baby’s head slightly changes its shape and size due to the displacement of the bones of the skull. This ensures optimal passage through the birth canal.

And after birth, the fontanel area allows the brain to grow and develop freely.

In addition to facilitating the process of labor, these non-ossified areas are necessary as:

• natural shock absorber in cases of falling or hitting the head, which is not uncommon, since the baby has not yet developed a sense of self-preservation, and therefore nature itself took care of protecting the crumbs;
• a temperature regulator - for the release of excess heat (the very mechanism of heat control in infants is still imperfect, and it takes some time to adapt in the world outside the mother’s womb);
• as well as for the diagnosis of possible brain problems using ultrasound, which has become the norm of medical practice in recent times.

What should be the fontanel in a newborn

The front non-ossified area resembles a rhombus shape, and its dimensions, according to average indicators, vary from 25 to 30 mm. During the very first month of life, it can increase slightly, due to a change in the shape of the skull itself after childbirth and the subsequent growth of the brain. Starting approximately from the age of four months, the process of reducing the shape of the fontanel in the newborn begins.

The back non-hardened area resembles a triangle, and its dimensions are significantly smaller than the front - usually no more than 7 mm.

The size of the sphenoid and mastoid fontanelles is small - 6-10 mm, they also have a trigonal appearance.

Why do the indicators of the norm of fontanelles in newborns depend on?

First of all, the regulation of calcium-phosphorus metabolism in the baby’s body plays a huge role, which, in turn, is due to the nutrition of the woman herself during pregnancy. So, exceeding the norm of calcium and, as a consequence, the probable early ossification of the bones of the skull leads to a complication of passage through the birth canal.

Also, the size of this area in newborns also depends on the degree of full-term: in children born on time, the fontanel, as a rule, is smaller, in contrast to immature babies.

In the future, its value is subject to such factors as the age and characteristics of the metabolic process in the child's body, as well as the presence of any disease (neurological or metabolic).

Bulge and hollow as anomalies of development

By themselves, these phenomena are not yet a pathology, since they can be caused by the anatomical structure of the brain or other factors. It is important to understand the nature and severity: an abnormally sunken, or protruding, pulsating area should be alerted, especially if these symptoms are accompanied by fever, convulsions, etc.

What circumstances can provoke such deviations?

1. The size of a large fontanel in a newborn can exceed the normal range and protrude above the surface:

• with prematurity;
• due to a violation of the process of bone formation;
• be the result of excessive accumulation of fluid in the brain.

If the baby has a progressive fontanel growth, accompanied by a divergence of the sutures of the skull, this is an occasion for an early consultation with a neurologist.

2. Or the fontanel in a newborn can sink, be sunken. This is usually observed:

• in transferred babies ;
• due to insufficient fluid in the body.

It should be remembered that this condition can be dangerous for the baby, and you need to seek specialized help.

Fontanel ripple

It is an absolutely natural phenomenon from the point of view of anatomy: the baby’s heart contracts and transmits oscillations of the cerebrospinal fluid that passes through the membranes of the brain, and since the coating of this non-ossified area is relatively thin, if you touch it lightly, you can feel the fontanel in the newborn pulsate. This is similar to pulsation of the carotid artery in an adult.

Her character changes with each month of the baby's life:

• at the very beginning it is quite pronounced;
• approximately by 4 months it becomes less noticeable;
• at 6 months, the ripple is still distinguishable and obligatory, but already acquires a more calm, even character.

Parents should remember that any change in behavior, whether it is crying and tears of pain or cries of joy, affects the nature of the pulsation of the fontanel in the direction of increased rhythm.

Dangerous pulsation-related symptoms

What can be considered an unhealthy pulsation of the fontanel in a newborn and cause for excitement?

We can distinguish the following main, but not absolute list of signs:

• rapid rhythm, especially associated with the convexity of the fontanel in the baby, as a rule, indicates an increase in intracranial pressure;
• intermittent, frequent changes in the rhythm may be a symptom of a disease of the cardiovascular system;
• the absence of pulsation, especially associated with the involvement of the fontanel, is a signal of a beginner or progressive dehydration of the body.

Overgrowing Dates

A large fontanel in a newborn, as a rule, is delayed by a year, but sometimes some deviations from this indicator are possible in the direction of increasing the period of overgrowth - up to one and a half years. This should not cause concern on the part of the parents if other parameters of the health assessment are in line with the norm.

Nevertheless, there are certain standards that reflect adequate closing times for the “window” for months of development of the baby. Below is an indicative table of sizes in trimesters with a progression of fontanel reduction.

A small fontanel in a newborn, as a rule, is already closed by the time the child arrives in this world. But there are times when its delay takes place within two to three months after birth. This is also the norm, again with adequate indicators for other parameters of the baby’s health.

What determines the closing time of fontanelles?

In fact, this phenomenon is individual in nature, like all other features of the development of the child, whether it is the first steps of the baby, teething of the first and subsequent teeth, or the development of speech.

Based on observations of healthy children, the following data on the closure of the anterior fontanel were revealed:

• 1% - in three months;
• 40% - per year;
• 59% - in the area of ​​two years.

Nevertheless, speaking about objective factors affecting when a fontanel in a newborn grows, experts point out a lack of calcium with vitamin D, which can slow down the process of tightening the "breathing" islet. These elements form the basis of bone solid and are indispensable for the intensive growth of the child's body.

At the same time, their excessive content leads to the rapid closure of the "window", which is why under certain circumstances a baby may experience intracerebral hemorrhage.

As evidenced by the slow pace of closure of the fontanel

If the "breathing" area on the top of the head tends to stretch the solidification period, this may indicate the development of certain diseases, such as:

• rickets, as the most common;
• thyroid dysfunction;
• hydrocephalus, or the accumulation of excess fluid in the brain;
• genetic pathologies of various origins (glass man syndrome, Down syndrome, others).

Possible reasons for its early closure

Sometimes the time when the fontanel in a newborn overgrows comes a little earlier than the set deadlines, in 7-10 months, which is not a pathology in an absolutely normal developing child.

But first, it is worth excluding possible diseases:

• craniosynostosis - a rare disease of the child’s skeletal system, characterized by deformation of the brain of the skull;
• microcephaly is a weak development of the brain relative to other parts of the body.

Respect

This tiny area does not require special care, and you should not be afraid to touch it while washing the baby’s head or combing it. With a simple light touch, the fontanel structure cannot be damaged in any way: it is a rather dense formation, despite the fact that it looks easily vulnerable and fragile.

A gentle gentle massage with a special children's brush is also useful, as it activates blood circulation and hair growth.