Have you ever noticed the white, creamy substance covering a newborn’s body? Almost like cream cheese? Depending on who you ask, you either get “Eww, gross!” or “Wow, amazing!”
It’s called Vernix Caseosa, or simply vernix. This coating develops in utero through the sebaceous glands around 20 weeks gestation and forms a protective layer on the baby’s skin. With it’s waxy, waterproof properties, it keeps their skin moisturised in the amniotic fluid - without it, their skin would look as if they’ve had a long, hot bath: like a shrivelled up prune.
Vernix mainly consists of shed fetal skin cells, fetal skin oil and shed lanugo, the fine hair that babies grow in utero all over their bodies. Did you know, 61% of the proteins found in vernix can’t be artificially replicated and are not found anywhere else? It’s that special!
Babies born between 38 and 40 weeks gestation have on average the highest amount of vernix while pre-term (<37 weeks) and post-term infants (>42 weeks) usually have the least amount.
For a long time, it was common place in hospitals that babies were taken away almost immediately after birth, weighed, cleaned and given back to the mother clothed and presentable. We have since learned a lot and the World Health Organisation in fact recommends NOT cleaning babies after birth but leaving the vernix on and delaying that first bath for at least a few days!
Far from being gross or an unpleasant side-effect of pregnancy, the vernix coating your baby plays an important role and has immediate and long term benefits for your baby:
It lubricates the baby on it’s way through the birth canal
It moisturises baby’s skin after birth (don’t wash it off, rub it in!)
It forms a protective barrier and is antimicrobial (this study showed that its properties are actually similar breastmilk), inhibiting the growth of pathogens and promoting healing
It facilitates the colonisation of the skin and gut with good bacteria to form a healthy microbiome
It contains high amounts of Vitamin E (remember that expensive moisturiser you bought?), which is an amazing antioxidant. Have a read here, this study (published in 2005), showed that babies who kept their vernix on had healthier skin and also a higher body temperature.
It helps newborns to maintain their body temperature, along with skin-to-skin that’s all they need. No requirement for a hat.
So what about post-term infants? When a baby’s lungs mature, they release a surfactant that mixes with the amniotic fluid which then emulsifies the vernix - causing it to shed from the skin. It is then ingested by the baby with the amniotic fluid so they do get all the goodness as well, building up an immune defense from the inside.
Right, so when IS a good time to bathe your baby? Delay it for as long as you like! It’s obviously totally up to you. If you just want to wash a bit of blood off, you can use a warm wet cloth. Most of the vernix will absorb into baby’s skin within the first 24 hours but if you want it all absorbed, wait for about 5-6 days. If you want to keep the vernix on your baby, make sure you ask your midwife not to rub it off.
Does it smell? Only if you think a newborn baby smells bad! Vernix is probably the cleanest substance there is and also plays a part in giving your newborn that yummy baby smell.
What do you think? Gross or amazing?