Week Eighteen

Return to Fetal Development Overview

  • Vernix (a white cheese-like protective material) forms on baby's skin with the lanugo (soft, lightly pigmented hair covering the body and limbs); both serving to protect your baby's skin during the months in water.
  • Your placenta continues to grow and nourish the baby. Don't forget those prenatal vitamins!
  • Tiny air sacs called alveoli begin to form in lungs. He'll be putting these lungs to good use in just a few months!
  • Her vocal chords are formed. She goes through the motions of crying but without air she doesn't make a sound.
  • Features of your baby's heart, including ventricles and chambers, should be visible during an ultrasound.
  • Your baby measures about 5.59 inches (14.2cm) this week and weighs about 6.7 ounces (190gm).

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