If you have seen a new-born, you may have noticed a white-ish creamy substance on them. People react differently when they see this, and some find it icky, insisting that the baby be cleaned up fast. The strange coating is called vernix caseosa, a white, creamy, naturally occurring biofilm covering the skin of the foetus during the last trimester of pregnancy. The coating on the neonatal skin protects the new-born skin and facilitates extra-uterine adaptation of skin in the first postnatal week if not washed away after birth, according to the US National Library of Medicine National Institutes of Health. 

"Some new-borns have less while others have a lot of it all over the body. The coating is influenced by different conditions, like the grease in the womb depending on the food the mother has been eating while carrying the baby,” says Delphine Umugwizawase, a midwife at the University Teaching Hospital of Kigali (CHUK). 

She adds that the protein intake of an expectant mother is a root influence that leads to vernix caseosa’s volume inside the womb.  

Why you should wait to clean vernix coating

New-born babies are wet from the amniotic fluid and can easily get cold. Vernix caseosa prevents heat loss when not washed immediately after the birth, Umugwizawase says. 

Vernix coating on the neonatal skin protects the new-born skin in terms of moisturising and facilitates extra-uterine adaptation of skin in the first postnatal week, since they have spent nine months surrounded by amniotic fluid in the womb that could lead to non-skin exfoliation as adult’ skin does. Instead, a new-born’s skin may look dry and begin to peel off, experts say. 

The strategic location of the vernix on the foetal skin surface suggests participation in multiple overlapping functions required at birth, such as barrier to water loss, temperature regulation and innate immunity.

Research proved that 61% of the protein found in vernix can’t be artificially replicated and are not found anywhere else on living objects. That is why they advise cleaning babies at-least two hours after birth. According to the World Health Organisation (WHO), babies who are bathed too soon after birth are more likely to become cold and could develop hypothermia, the condition of having an abnormally low body temperature.