Vernix caseosa, one of those things about a newborn baby that when you first hear it you will say ‘wait, I don’t know about that one for sure’. Let’s have a look at all there is to know about vernix caseosa.

What is vernix caseosa?

Vernix caseosa is a protective layer on the baby’s skin during pregnancy. Vernix begins developing around 16-17 weeks of pregnancy and will be protecting the baby’s delicate skin until the last weeks of pregnancy or until a few hours after birth depending on when the baby is born.

Vernix caseosa is a white substance that comes from the amniotic fluid and the baby’s own sebaceous glands and it covers the delicate baby’s skin.

Vernix starts developing during the second trimester of pregnancy.

What is the function of vernix?

During pregnancy baby’s development takes place at all levels. Baby’s skin is very delicate and the amniotic fluid plays a pivotal role in protecting your baby’s delicate skin. As your baby develops inside a bag full of fluid it’s almost constantly on the move, not spending too much time on the same part of the body so the skin is constantly protected. Vernix adds to this skin protection an extra protective barrier as a greasy substance full of good fatty acids with antioxidant properties that act as a protective biofilm against bacteria and other microbes.

During birth vernix coating acts as a lubricant for the baby to navigate the birth canal.

Once the baby is born the vernix acts like a natural moisturizer that will protect the newborn’s skin during the first few hours after birth until the mother’s bacteria fully colonizes the baby’s skin.

Baby born with lots of vernix

As the main function of the vernix caseosa is to protect the baby’s skin while developing in the womb the amount of vernix covering the baby’s skin will be reduced at the end of the third trimester as the due date approaches. Sometimes, some babies are born with a lot of vernix caseosa. Babies born covered in vernix are usually born before their due date.

In preterm babies born weeks before reaching full-term vernix plays a very important role in protecting the preterm newborn’s skin as not only it has antimicrobial properties and other innate immune proteins. Vernix caseosa acts as a protective coating against any bacterial infections during the first hours following birth when a premature baby is most vulnerable. Vernix coating also provides a hydrophobic barrier preventing sharp changes in body temperature preventing heat loss and dehydration. Leaving the vernix on your newborn’s skin will help the little one regulate her own body temperature while keeping nasties at bay.

Baby born without vernix

Do not worry if your baby is born without vernix caseosa. This protective layer helps the baby develop in the womb. If your baby is born without vernix it means it’s not necessary any longer. Vernix has already fulfilled its purpose and the baby’s skin is completely ready to face life outside the womb without vernix. Full-term babies and those babies born after the 40th week of pregnancy are usually the ones born with less vernix on their skin. Some babies who are born near the 42 week of pregnancy not only have no vernix but the skin of their feet is starting to peel off. There’s nothing to worry about but you may have noticed if your baby has been ‘cooking’ for a long time. Read more in 42 Weeks Pregnant – What To Expect This Week and 15 Self Care Tips For 42 Weeks Pregnant Mamas

Do C-section babies have vernix?

The amount of vernix a baby is born with depends mainly on the amount of vernix the baby has at that point. As the end of the pregnancy approaches, the baby’s skin is fully formed and ready to protect the newborn’s skin after birth, the amount of vernix is reduced as the baby’s skin absorbs the vernix.

Babies born by C-section may have a good amount of vernix caseosa especially if the cesarean section was elective.

When a baby born by c-section has a lot of vernix this may be an indicator of the baby’s natural birth date being still far away from the date the c-section takes place.

As many elective sections are done before forty weeks it’s quite common to see a cesarean section newborn skin covered in vernix right after birth.

This vernix coating will help the newborn adapt better to extrauterine life

Why does vernix smell so good?

A baby is the most immature newborn of all mammals. A human baby needs mama much more than any other baby mammal. For this reason, human babies develop a series of strategies to be well cared for while they grow a bit more independent.

This means producing pheromones that will trigger the mother’s oxytocin production. Oxytocin is the love hormone and babies and new mothers need a lot of it for the development of secure bonding and attachment. The amniotic fluid and the vernix caseosa are full of baby’s skin cells that keep the marvelous baby smell.

The smell inside the uterus will guide the baby towards food after birth. During pregnancy, the baby sucks her fists and fingers frequently. This way, the baby practices sucking and tasting. The amniotic fluid and the vernix taste very similar to breast milk.

A baby that has been smelling and licking fluid in utero will most likely repeat those actions after birth. Vernix helps retain that smell for the first few hours after birth and the smell will lead the little one towards the breast.

What are the benefits of not washing off vernix?

Leaving the vernix on your newborn’s skin has a lot of health benefits.

You may feel inclined to wash vernix off the baby’s skin, especially if the baby passes meconium at or right after birth. You may gently wipe the dirty area with a wet cloth gently rubbing the meconium and trying to leave as much as possible of the vernix on the baby’s skin.

The World Health Organization highlights the importance of keeping vernix caseosa on the skin and the relevance of skin-to-skin contact in regulating body temperature and appropriate bacterial colonization.

Vernix caseosa will protect the baby from temperature fluctuations, from any unwelcome bacteria from the birth canal, or from the environment around the baby. Our biome is the amount of healthy bacteria that first colonizes our gut.

Vernix caseosa plays a very important protective role in developing the most thriving biome as the baby’s shed skin cells act as a protective layer against adverse microbes especially during the first few days of life until breastfeeding is well established and the immune system is well boosted by colostrum.

Try and delay the baby’s first bath as much as possible. The more vernix your baby’s skin can absorb the better. A baby’s delicate skin doesn’t need soap and water and vernix removal should be out of the picture. Once your baby is feeding well you can give the baby a sponge bath. The first bath should be delayed as much as possible and should never be done immediately after birth. Can you wait several weeks before you do that?

You can gently wipe the areas that need it with a damp soft cloth and wait for the first sponge bath until the little one is a few weeks old. This way you’ll make sure you keep vernix intact so your baby gets all those vernix benefits. Delayed bathing will just help your baby keep that protective antimicrobial cover that will also prevent the little one from getting dry skin.