Vernix Caseosa refers to the substance that’s beginning to coat your baby’s skin this week. From the Latin words vernix meaning, “varnish,” and caseosa meaning, “cheesy,” this protective substance is secreted by your baby’s sebaceous glands. As the Latin names reflect, the coating is a white, cheesy substance made up of oil and sloughed off skin cells. Though it sounds pretty nasty, this coating is very important.

First, it protects your baby’s skin from becoming chapped. You’re wrinkly after an hour in the tub—imagine how wrinkly your baby would be after nine months in amniotic fluid without vernix caseosa! Doctors have discovered there are proteins in the oils that have antibiotic properties, protecting your baby from infection. They’ve also discovered that the vernix serves to clean the skin in the womb and actually does a better job than a store-bought cleanser. Finally, having a greasy substance on your baby should help ease the way down the birth canal.