Week 21

  • Sensory systems continue developing. Lips are sensitive, baby may stick out tongue.
  • Eyelashes and eyebrows are well formed.
  • Permanent teeth buds are apparent in the gums.
  • Baby can now hear and recognize mother’s voice, breathing and heartbeat.

Week 22

  • Baby weighs about 1¼ pounds and measures about 12 inches from head to heel.

Week 23

  • Breathing motions may occur up to 44 times per minute. The lungs produce a substance necessary for breathing after birth.

Week 24

  • Sudden, loud noises may trigger a blink-startle response, which may increase movement, heart rate, and swallowing.
  • Baby weighs almost 2 pounds and measures about 14 inches from head to heel.
Fetus at 20 weeks.

Baby at 20 weeks.