Physical portrait of the newborn.
Welcoming a child is a unique sensory encounter. This guide details every physical characteristic of your baby, transforming curiosity into serene and informed knowledge.
A morphology radically different from that of an adult
At birth, your child's body is not simply a miniature version of yours. It is an organism perfectly adapted to its intrauterine life and the delicate transition of delivery. The first thing that strikes you is the apparent disproportion: the head represents about a quarter of the total body length, compared to an eighth in adults.
The forehead is prominent, the nose often slightly flattened to facilitate breastfeeding, and the trunk appears bulky with a slightly swollen abdomen. These characteristics, although surprising, are evidence of intense brain development and robust organic vitality.
Head/body ratio
Average height at birth
"Every physical detail is a signature of their new life."
The skull: a masterpiece of flexibility
Understanding fontanelles and temporary deformations after delivery.
Fontanelles
The skull is not yet fused to allow for the rapid growth of the brain. There are two soft zones: the anterior fontanelle (diamond-shaped) and the posterior one (smaller). They are essential and should not be feared if touched gently.
Their evolution at 1 month →Skull Molding
During passage through the pelvis, the bones of the skull can overlap. It is common for a baby to be born with a "sugar-loaf" shaped head or with a caput succedaneum (soft swelling). Everything naturally returns to order within a few days.
Cephalohematoma
Sometimes, a small accumulation of blood forms under the periosteum. It is a firmer lump that does not cross the bone sutures. Although it may cause concern, intervention is discouraged: it will disappear on its own within a few weeks.
The gaze and the first hair
Eyes full of mystery
At birth, the eyelids are often swollen due to the effort of delivery. The final color is rarely fixed: most infants are born with eyes of an indeterminate blue-gray. It is only around 6 to 9 months that the final pigmentation will be revealed. Also, note that the newborn does not yet produce tears when crying; their tear ducts will be fully functional in a few weeks.
The mystery of the hair
Some babies are born with a full head of hair, others are almost bald. It is common to observe hair loss in the first weeks (neonatal effluvium) due to the drop in maternal hormones. Do not worry: regrowth is systematic and often has a different texture.
Learn more about sensory awakening →
Simulator: First Day Special Features
Click on an area to discover your baby's physiological secrets.
Select an area
Use the interactive points on the silhouette to get detailed and reassuring information about neonatal physiology.
The skin: an organ in transition
Fragile, thin, and sometimes covered in surprising substances, a newborn's skin tells the story of its transition from an aquatic to an aerial environment.
Vernix Caseosa
This white, fatty substance protects the skin against amniotic fluid. No need to rub it off vigorously; it is absorbed by the skin.
Lanugo
A fine down that sometimes covers the back and shoulders, especially in babies born slightly early. It falls off in a few days.
Physiological jaundice: frequent and often mild, related to bilirubin.
Skin Phenomena
- • Milia: Small white spots on the nose, simple clogged sebaceous glands.
- • Angiomas: "Stork bites," often on the back of the neck or eyelids.
- • Mongolian spots: Bluish spots on the lower back, common on darker skin tones.
- • Seborrheic dermatitis: Due to hormones, it resolves on its own.
Focus on jaundice
Appearing around the 2nd or 3rd day, jaundice is caused by an accumulation of bilirubin. If it is too pronounced, phototherapy (exposure to blue light) will help baby's liver eliminate it. This is a common process that should not alarm you, but requires rigorous clinical monitoring.
The trunk and limbs
The Umbilical Cord
The last physical link with intrauterine life, the umbilical stump will dry, blacken, and fall off in 5 to 15 days. It only requires gentle cleaning and careful drying. Monitor for any redness or suspicious odor.
Mammary swelling
Under the influence of maternal hormones, it is common for newborns (boys or girls) to have slightly swollen mammary glands. This is transitory.
Genital particularities
In boys, the scrotum may appear bulky (hydrocele). In girls, the labia majora may be swollen. Small secretions are normal.
The "C" posture
Baby often keeps their legs and arms tucked, turned outwards. This is the memory of their fetal position. Their limbs will lengthen and tone up over the weeks. No straightening is necessary: let nature do its work.
Explore motor skills →
The initial clinical examination: absolute safety
Within the first 24 hours, a pediatrician or midwife performs a complete examination. This is not just a technical check, it is a moment of dialogue to address your concerns.
01 Cardiorespiratory Assessment
Listening to the heart (rate, rhythm, murmur) and monitoring breathing. A baby's breathing rate is faster and sometimes irregular.
02 Orthopedic Maneuvers
The Ortolani test checks hip stability and screens for potential congenital dysplasia.
03 Neurological Examination
Observation of tone and archaic reflexes (sucking, grasping, automatic walking).
04 Mouth Inspection
Checking the palate, the tongue-tie, and detecting any "neonatal teeth" or small benign cysts (Epstein pearls).
"This examination is the perfect opportunity to ask all your questions about your child's appearance."
Details of birth examinations →Vigilance without alarm
While the majority of physical signs are normal, certain points merit a prompt consultation for your peace of mind.
Skin Signs
- • Pallor or persistent bluish coloring
- • Very early jaundice (less than 24h)
- • Purpuric skin rash (small red spots)
General Signs
- • Excessive sleepiness or incessant crying
- • Absence of urination (urine) after 24h
- • Red, hot, or purulent umbilical cord
In case of doubt, trust your instinct and contact your pediatrician or the maternity ward.
Frequently Asked Questions
Why does my baby have blue hands and feet?
This is called acrocyanosis. It is caused by a still-immature circulatory system that prioritizes vital organs. If the rest of the body is pink, it's perfectly normal.
When will the shape of their head stabilize?
Most birth-related deformations disappear within 2 to 3 weeks. The fontanelles, on the other hand, will close progressively between 9 and 18 months.
Can I wash off the vernix?
It is not recommended to rub it off. It is a natural protective barrier against infections and an excellent moisturizer. It will be absorbed by baby's skin in a few days.
Accompanying every step.
Your baby's physical portrait is just the beginning of an extraordinary adventure. Continue exploring their development with our expert guides.