How Many Bones Do Babies Have?

Written by Emmanuel Kingsley
Published: May 10, 2022
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Growth is an important aspect of human development, and every newborn matures into an adult at some point in their life. Irrespective of gender, color, or race, every child has a similar body structure at birth.

This article will reveal some interesting facts about babies’ bones. Let’s get started.

How Do Babies’ Bones Form?

The basic structure of a baby’s bones begins at the early stage of pregnancy as cartilage, a tough yet flexible tissue that solidifies into bone over time. And their flat bones (the skull, collarbone, some facial bones, and sections of the pelvis) begin as thin tissue sheaths known as membranes.

When Does The Number Of Bones In Infants Change?

As babies begin to grow, the fusing process of the bones (ossification) begins, and numerous microscopic bone fragments join together to form a single bone. Fascinatingly, it is a continuous process between the sixth and seventh week of embryo development until around age 25. 

How Many Bones Do Babies Have?

baby skeleton anatomy

©Life science/

At the time of birth, a baby’s body contains approximately 300 bones. However, 176 are actual bones, and the rest are all hyaline cartilage models that develop into bones as the child grows by endochondral ossification. Courtesy of the endochondral ossification and the help of calcium-enriched foods, the embryonic cartilaginous model found in babies gradually metamorphosizes to 206 firm bones found in adults. Babies’ kneecap (patellae) is one great example of cartilage fusing to form a hardened framework. This flat and rounded bone (kneecap) which articulates with the thigh bone, fuses to become a bone in children at age 10 or 12.

Why Are There More Bones In Babies Than Adults?

As babies grow, some of their bones fuse to become one.

©New Africa/

A baby has more bones than an adult because bones begin to fuse as humans grow into the adults. However, the first bones are mostly made of soft cartilage since the fetus has a limited space to grow in the womb. So, to avoid difficulty during delivery, the fetus must be flexible enough to travel through the vaginal canal. 

Is There Any Bone In a Baby’s Skull?

A baby’s head is made up of five skull bones.


The skull comprises a collection of interconnected bones, which includes two frontal bones, two parietal bones, and one occipital bone. Interestingly, these bones are connected by sutures needed for the infant’s brain development. During childbirth, these sutures permit the bones to overlap so that the child’s head can pass through the birth canal with ease while protecting the brain. However, as the infant grows older, these sutures become less flexible and act as fibrous bands of tissue that connect the bones of the skull.

What is a Fontanelle?

A fontanelle is a soft spot in a baby’s skull comprising soft membranous gaps (sutures) between the cranial bones essential for the proper development of an infant’s brain. There are 6 types of fontanelles present in infancy, but the notable ones include the anterior and posterior fontanelle. The posterior fontanelle typically closes at two months, while the anterior closes between 9 and 18 months.

Why Do Other Animals Except Babies Walk Immediately After Birth?

Animals such as giraffes, lambs, horses, baboons, and even humans’ closest evolutionary relatives, chimpanzees and bonobos, walk a few hours after birth. Unfortunately for human babies, their bones contain several soft, flexible cartilages which do not grant them the agility to walk immediately after birth. However, as they grow older and the muscles in their legs strengthen, babies gradually learn to crawl, walk, and move more efficiently. 

What is a Cartilage?

Cartilage is a soft connective tissue that is avascular and has a less organized microarchitecture framework than bone. It protects and covers the ends of long bones at joints and nerves. It is a resilient, smooth, elastic tissue found in the ears, rib cage, nose, and other body regions. Three main types of cartilages differ in relative amounts of collagen and proteoglycan, including the elastic cartilage, hyaline cartilage, and fibrous cartilage.

The elastic cartilage is found in the external ear flaps and portions of the larynx. The hyaline cartilages are found in the nose, ears, trachea, parts of the larynx, and smaller respiratory tubes, while fibrous cartilage can be found in the spine and menisci.

Are Teeth Bones?

Although teeth and bones have similar calcium components, they are not classified as bones since tooth enamel cannot heal itself or grow back if broken.

Is It Normal For A Baby To Be Born With Teeth?

Between the ages of 4 and 7 months, most babies begin to develop their first tooth. The central incisors, which are the middle and bottom teeth, are usually the first teeth to break through the gums. However, some babies are surprisingly born with one or more teeth called “natal teeth” – extremely rare, appearing mostly 1 in every 2,000 – 3,000 births.

How Many Set Of Teeth Do Babies Have? 

More often than not, a baby is born with no teeth. However, at four to seven months old, a baby’s first teeth (usually the upper and lower incisor) appear. Interestingly, a complete set of 20 teeth hidden beneath the gum in the jawbones begin to surface between 2 and 3 years, while their permanent teeth appear between 6 and 7 years.

Babies develop the following teeth before transcending as adults:

  • 4-second molars
  • 4 first molars
  • 4 canine teeth
  • 4 lateral incisors
  • 4 central incisors

How To Keep Babies’ Teeth Clean.

It is important to keep babies teeth clean to protect against infection, cavities, and pain. To achieve this, one must constantly run a clean damp washcloth over the gums to clear away harmful bacteria that can cause decay or damage the permanent teeth underneath.

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X-ray Whole Thoracic Lumbar Spine lateral baby
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