Baby hair loss is a common phenomenon for new parents who may notice hair shedding in the first few months. While seeing a full head of newborn hair thin out can be alarming, the change is a normal part of infant development. The hair grows back as a natural transition to the child’s permanent hair. This shedding is merely a temporary phase in the hair growth cycle.
Why Babies Lose Their First Hair
The initial hair loss experienced by infants is primarily due to a dramatic biological shift following birth. While in the womb, the baby is exposed to high levels of maternal hormones that support the hair follicles in their active growth phase. After delivery, the sudden drop in these hormones triggers a synchronization of the hair cycle, causing a large number of follicles to enter the resting or telogen phase simultaneously.
This temporary, widespread shedding is known as telogen effluvium, and it generally peaks around two to three months of age. During this process, the hair follicles temporarily “slow down” and stop producing new strands, leading to noticeable hair loss. The phenomenon is similar to the postpartum hair loss many new mothers experience, as both are linked to the same hormonal fluctuations.
Separately, many babies develop a bald spot on the back of the head, a localized hair loss called friction alopecia. This is a mechanical issue caused by the constant rubbing of the scalp against surfaces like crib sheets, car seats, or swings. Since infants spend a significant amount of time lying on their backs for safe sleep, the friction from movement can wear away the delicate hair in that area. This type of hair loss is not hormonally related and is a physical consequence of a baby’s limited mobility.
How Long Until New Hair Appears
The regrowth timeline varies considerably from one infant to another, but the new hair typically begins to appear shortly after the shedding starts. The hair loss phase, or telogen effluvium, is temporary and self-correcting, meaning the hair follicles are already preparing to restart the growth cycle. Most babies will begin to fill out their scalp with new hair within the first six months of life.
For the localized bald spots caused by friction, the hair usually starts to return once the infant gains more mobility. As the baby learns to roll over and spends more time upright, the mechanical irritation of the scalp decreases, allowing the hair to grow back. Parents can generally expect the scalp to be fully covered by the child’s first birthday, though some may take slightly longer.
The initial hair a baby is born with is often fine lanugo, which is typically shed before or shortly after birth, or soft vellus hair. The new strands that grow in are a different type, known as terminal hair. Terminal hair is thicker, more pigmented, and has a longer growth phase than the original fine fuzz.
Changes in Color and Texture
The new hair that grows back often possesses completely different characteristics than the hair a baby was born with. Hair color is determined by a pigment called melanin, produced by cells called melanocytes within the hair follicle. The amount and type of melanin—eumelanin for brown/black hues and pheomelanin for red tones—are what ultimately dictate the shade.
When a baby is born, the melanocytes may not yet be fully activated, or they may be producing lower concentrations of pigment, resulting in lighter hair. As the child develops, the activity of these pigment cells can increase, leading to a gradual darkening of the hair color. Genetics play a defining role, determining the eventual color and texture of the hair.
The texture also transforms as the fine vellus hair is replaced by the more substantial terminal hair. This change can mean the soft, straight hair of infancy is replaced by coarser, thicker strands, or that a slight wave turns into a more defined curl pattern. These shifts are normal and genetically predetermined, representing the child’s permanent hair phenotype.