Almost everything you will see on your baby's skin is normal
In 594 US newborns examined by skin specialists in the first 48 hours, most had at least one finding parents mistake for illness.
Nobody prepares you for what a newborn looks like. You are handed a baby and left to interpret its skin yourself, and much of what you see looks, to an untrained eye, like disease.
The best US source is a study of 594 babies in San Diego, examined in the first 48 hours of life by paediatric dermatologists rather than by parents or general clinicians. Here is what they found, with that denominator attached to every row.
| What you may see | Also called | Found in 594 US newborns |
|---|---|---|
| Nevus simplex | Salmon patch, stork bite, angel's kiss | 83% |
| Sebaceous gland hyperplasia | Tiny yellow-white bumps on the nose | 42.6% |
| Dermal melanocytosis | Flat blue-grey patch, often on the lower back | 20% |
| Milia | White pinhead spots | 8% |
| Erythema toxicum neonatorum | Blotchy red rash with small pale centres | 7% |
| Infantile hemangioma (by 3 months) | Strawberry mark | 4.5% |
| Congenital melanocytic nevi | Brown birthmark present at birth | 2.4% |
| Cafe-au-lait macules | Flat light-brown patch | 2% |
Four in five newborns in that study had a stork bite. More than two in five had the little yellow bumps. These are not conditions. They are what newborn skin is.
One rate this guide deliberately will not give you as a single number. Erythema toxicum, the blotchy rash that appears in the first days and frightens parents most, was found in 7% of those 594 US babies. In two Brazilian studies of 2,831 and 2,530 newborns, also examined by dermatologists in the first 72 hours, it was found in 21.3% and 23%. Two careful prospective studies differ threefold and neither explains why. So: somewhere between about 1 in 14 and about 1 in 4 (those conversions are arithmetic done here), depending on the population, and it is benign and self-limited in all of them. In the Brazilian data it was actually more common in babies with good Apgar scores, no pregnancy risk factors and no intensive care admission. It is a finding of the well baby.
The two numbers that settle the whole question. In that Brazilian study of 2,530 newborns examined in the first 72 hours, 95.8% had some skin finding. Of the whole group, 0.5% had a skin malformation and 0.1% had a skin infection. Five in a thousand, and one in a thousand. Everything else visible on a newborn's skin was normal or temporary.
"Which of these will go away on their own, and roughly when?"
"What would look different enough that I should call?"