Lanugo is a thin layer of hair that covers the baby’s body inside the mother’s womb . It begins to occur around the 13th week of gestation, and although at first it is only present in the head, little by little it will spread to the rest of the body.
In the last weeks before delivery the lanugo begins to disappear, although some babies – especially if they are premature – can be born with areas of their body covered with lanugo, sometimes being quite long and dark.
We tell you what function the baby’s lanugo fulfills within the mother’s womb.
What is lanugo and what does it do?
The lanugo is a fine, soft and little pigmented hair that grows on the body of the fetus . It is part of the vernix caseosa or sebaceous daub, and its function is to protect the delicate skin of the baby in the absence of subcutaneous fat.
Lanugo begins to form between week 13-14 of gestation in the head of the fetus, and around week 20 it is already present in all parts of the body. Around week 39-40 it will begin to shed inside the uterine cavity , and its villi will be suspended in the amniotic fluid contributing to the formation of meconium.
Why are some babies born with lanugo?
Although most full-term babies no longer have lanugo, in some cases it is possible to see this layer of hair on their skin, especially if it is a premature baby. In these cases, lanugo tends to be visible on the scalp, ears, temples, cheeks, shoulders, and back, and can even be especially long and dark.
Although this phenomenon may surprise parents, there is no reason to worry nor does it require special attention, beyond the care that the newborn’s skin needs.
Lanugo has nothing to do with the body hair that we all have, and it is so weak and fragile that it will shed on its own in the first weeks of the baby’s life with the simple touch of clothing or the crib.
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