Your developing baby – week 30

by Kaiser Permanente |
Fetus at week 30, illustration

Your baby weighs about 3 pounds and continues to gain half a pound each week until birth. They're up to 15.5 inches long now and about the size of a cabbage.

Fat deposits spread and fill out under your baby’s skin, making the skin appear smoother. These fat deposits also help the baby stay warm after birth.

During week 30, your baby continues to:

  • Continues to swallow and pass urine into the amniotic fluid.
  • Practice breathing. You may even see this movement on ultrasound
  • Develop brain tissue.
  • Grow bone tissue. Your baby will have over 300 bones at birth.
  • Produce red blood cells from bone marrow.
  • Develop lungs, digestive tract and other major organs.

This article has been created by a national group of Kaiser Permanente ob-gyns, certified nurse-midwives, pediatricians, lactation consultants and other specialists who came together to provide you with the best pregnancy, birth, postpartum, and newborn information.

Some of the content is used and adapted with permission of The Permanente Medical Group.