Many new parents are surprised and concerned when their newborn begins to lose hair shortly after birth. This phenomenon is extremely common and a normal part of infant development. The initial hair, often referred to as “fetal hair,” is simply being shed to make way for permanent hair growth. This process is a natural physiological adjustment as the baby adapts to life outside the womb, and almost all babies experience some degree of hair loss in their first few months of life.
The Primary Causes of Newborn Hair Loss
The most significant cause of widespread newborn hair loss is a dramatic shift in hormone levels immediately following birth. During pregnancy, high levels of maternal hormones, particularly estrogen, stimulate the hair follicles’ active growth phase (anagen phase). Once the baby is delivered, these maternal hormones rapidly drop, which triggers a large number of hair follicles to simultaneously enter the resting phase (telogen phase).
This synchronized change results in telogen effluvium, characterized by diffuse hair shedding that typically becomes noticeable around two to four months after birth. This hair loss is considered a non-scarring form of alopecia, meaning the hair follicles are not permanently damaged and will eventually resume normal function. This hormonal fluctuation is also why many mothers experience significant hair shedding postpartum.
Another common cause of localized hair loss is friction, which often results in a bald patch on the back of the baby’s head (neonatal occipital alopecia). Since infants spend much of their time lying on their backs for safe sleep, constant rubbing against surfaces like mattresses or car seats causes the strands to break off. This friction-related loss is most noticeable between three and six months of age, when babies start turning their heads frequently.
Some research suggests that even this localized occipital hair loss may be due to a physiological event initiated before birth, such as a localized telogen effluvium. Regardless of the exact mechanism, both hormonal shedding and friction are considered normal developmental occurrences.
The Timeline for Hair Regrowth
The shedding phase generally begins during the first six months of life, often peaking around three months of age. Once the hair follicles have shed, they immediately restart the growth cycle to produce new hair. The visible regrowth timeline varies widely among infants, depending on the speed of their individual hair cycle.
Noticeable regrowth can take several months. Full hair regrowth is typically seen by the baby’s first birthday, though for some children, it may take up to two years. The new hair often differs significantly from the original “fetal hair.”
The new hair may have a completely different color, texture, or thickness. For instance, hair that was thick and dark may regrow fine and light, or straight hair may grow back curly. While waiting for new growth, parents should adopt gentle care practices.
Gentle Hair Care Practices
- Avoid harsh brushing or combing and use only mild, baby-specific shampoos.
- For friction-related bald spots, alternate the direction the baby sleeps in the crib.
- Ensure the baby gets adequate tummy time while awake.
- Avoid tight hair accessories or ponytails to prevent unnecessary breakage (traction alopecia).
Signs That Warrant a Doctor’s Visit
While newborn hair loss is overwhelmingly normal, certain signs warrant a pediatrician consultation for an underlying medical condition.
If the hair loss is accompanied by a rash, redness, or extensive scaling on the scalp, this may suggest a fungal infection, such as tinea capitis (ringworm). Ringworm is uncommon in infants under two years old but requires oral antifungal medication for treatment.
Hair loss that occurs in perfectly smooth, round, or isolated patches may indicate alopecia areata. This is an autoimmune condition where the immune system attacks the hair follicles, and while rare in infants, it requires investigation. A consultation is also recommended if the baby shows other concerning symptoms, such as sluggishness, increased thirst, or pale skin.
The hair loss should be discussed with a doctor if it continues past the six-month mark without signs of regrowth, or if the baby’s hair has not fully grown back by their first birthday. Persistent or widespread hair thinning not explained by hormonal or friction causes should prompt medical evaluation.