Birth Terminology Explained: Vernix

There is a lot of terminology thrown around when you enter the world of pregnancy, birth, postpartum, breastfeeding, and parenthood. In this series, we're going to break it down, bit by jargony bit. 

The word for today is vernix.

What is Vernix? 

Official definition: Vernix, also known as vernix caseosa, is "a white cheesy substance that covers and protects the skin of the fetus and is still all over the skin of a baby at birth. Vernix caseosa is composed of sebum (the oil of the skin) and cells that have sloughed off the fetus' skin. 'Vernix' is the Latin word for 'varnish.' The vernix varnishes the baby. 'Caseosa' is 'cheese' in Latin."

(Source: MedicineNet)

Vernix is produced while baby is in utero starting around 21 weeks of gestation. 

When you will hear/see the term used? Vernix is one of the many ways to describe the appearance of a baby at the time of birth. Nurses, doctors, midwives, and childbirth educators may mention the presence and/or amount of vernix present on a baby at the time of birth. Vernix is described using words like oily, waxy, cheesy, creamy, white, thin, and thick. Whether vernix is present or not is neutral to baby's overall health. 

Why is it important/beneficial? Not all babies have vernix at birth. For example, babies born postterm aren't likely to have much or any vernix. Preterm babies are likely to have more vernix. Most babies born at or around term have varying amounts. Vernix serves many purposes, including:

• Protects baby's skin against moisture loss while in amniotic fluid in utero
• Protects against infections in utero
• Acts as a lubricant to help baby through the birth canal   
• Moisturizes skin after birth
• Helps colonize baby's gut
• May help regulate body temperature after birth

Understanding the roles vernix plays after birth allows you to make an informed decision about your baby's routine care immediately after birth. Many hospitals still routinely bathe babies soon after birth. Not only is this not necessary (babies are not born dirty, unless there is meconium -- stool -- present at birth), but it removes protective and beneficial bacteria and substances, like vernix. Using a soft, dry cloth to remove any remaining fluid and blood, without rubbing away vernix, is fine. Over the next day or two, rub the vernix into baby's skin prior to their first bath. 

If your place of birth routinely administers a bath right after birth, it's important you make your preferences known early and often. It's easy amid the chaos after birth for a bath to happen even if you want to avoid it. Tell the nurses on staff and make sure your partner/support person and doula knows.