Life Before Birth: Physical Development and Characteristics of Your Unborn Baby
BC Women’s Hospital & Health Centre p>Stage Three: Growing Through 29 Weeks to Birth

Fetal Age 29-32 Weeks
Approximately 16 inches (41 cm)
Weight 4lbs (1814 gms)

  • Your baby’s body is well formed and has a good change of survival if he or she is born now.
  • They will continue to grow and put on weight.
  • Their lungs become mature.
  • You may feel the baby hiccup as well as notice a change in the baby’s movements, moving side to side and rolling movement.
  • Baby begins to be able to focus and follow an object up/down and side to side.

Fetal Age 33-36 Weeks
Approximately 18 inches (46 cm)
Weight 5 ½ lobs (2500 gms)

  •  Your baby’s kidneys are fully mature and the liver is able to cope with some waste products.
  • The testicles have descended.
  • Accumulating antibodies.
  • The hair on their head may be 1-2 cms long.
  • Soft nail beds have grown to the end of fingers and toes.
  • Your baby will assume the birth position.
  • There is clearer movement and sleep patterns develop
  • Coordinating sucking, swallowing and breathing movements
  • Movements may indicate likes and dislikes of sounds.  Quiet movements may indicate baby likes the sound; very active or agitated movements may indicated dislikes.
  • Rapid development of vision; by 34 weeks baby has the full vision of a newborn and is able to follow objects in all directions.

Fetal Age 37-40+ Weeks
Approximately 20 inches (51 cm)
Weight 7-8 lbs (3175 – 3629 gms)

  • You’re in the home stretch now!
  • The vernix decreases, the nails grow longer and most of the downy hair is gone.
  • The baby continues to gain weight and could be born at any time now.
  • All the senses are developed and functioning.

Prepared by: Childbirth Education Curriculum Project Ad Hoc Committee
Approved by: BC Women’s Family Education Advisory Committee
May 1991, Revised December 2001