Prenatal Development

Third Trimester

Week 28: The baby's eyes begin to open and close.

Week 29: Baby's movements become more frequent & vigorous as its muscles and bones strengthen.

Week 30: Baby begins adding weight quickly--about 1/2 pound a week from now until week 37. Baby may practice breathing. If born now, the fetus can live outside of the womb and would be considered a premature baby.

Week 33: Baby's eyes can detect light. Due to space constraints in the womb, baby's movements will be less pronounced--in contrast with a few weeks earlier when kicks & jabs could actually be slightly painful.

Week 36: Baby's powerful sucking muscles are eager and ready to get to work.

Week 37: Your baby is considered full term and can enter the world at any time.

Week 40: This is considered the end of a typical pregnancy period. A baby's average weight at this time is 7.5 pounds.

Birth

When the baby is born, the placenta detaches from the uterus. The umbilical cord is then cut as the baby takes its first breaths of air. As the baby breathes, its heart and bypass arteries modify their functioning which then forces all of the baby's blood to now travel through the lungs where it will be oxygenized.

• Prenatal Development - First Trimester
• Prenatal Development - Second Trimester
• Prenatal Development - Third Trimester