May 31, 2021
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Trimester of Pregnancy
⟶ Updated 7 Dec 2017 ⟶
List of edits
Zygote is formed
Week 1-3: The egg is being fertilized
Week 4-6: The fertilized egg is in the womb.
Week 7-9: The brain is starting to develop.
Week 10-12: Eyes on the baby are starting to react to light.
Week 13-16: By week 13 you can hear the heartbeat.
Week 17-20: The eyebrows and eyelashes start to grow.
Week 21-24: The baby is “viable” around the twenty-fourth week.
Week 25-28: The brain, digestive system, and lungs are developed but not yet mature.
Week 29-32: The baby's head starts to move down.
Week 33-36: The nervous system is fully developed.
Week 37-40: The lanugo fur has disappeared. The baby is 3-4 kg.
Week 37-40: The baby's head moves farther down the pelvis.
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