What substance covers the baby’s skin during pregnancy, acting as a natural barrier?

The correct response is verix. This substance plays a crucial role during pregnancy by covering the baby’s skin in the womb. Vernix is a white, cheesy-like substance that protects the fetus’s skin from the amniotic fluid, preventing it from becoming too soft or damaged. It also has antimicrobial properties that help safeguard against infections.

In contrast, lanugo is a fine, soft hair that covers the fetus, particularly around 20 weeks of gestation, helping to keep the baby warm and sometimes assisting in holding the vernix on the skin. Amniotic fluid surrounds the baby and acts as a cushioning element, protecting it from impact but is not a barrier for the skin itself. Collagen is a structural protein found in connective tissues but does not serve as a coating for the baby’s skin during pregnancy. Thus, while all these components are important in prenatal development, only vernix serves as a natural barrier for the baby's skin.