Prenatal Timeline

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    First Trimester

    Egg becomes fertilized
    Zygote Implants into uterine wall
    Embryo begins to grow and look more human, neural tube forms
    All body parts start to develop by week 12
    Teeth, hair, nails develop
    Gender becomes apparent
    Heart begins to beat
    Baby weighs about 1ounce
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    Second Trimester

    Baby begins to stretch and move muscles
    Lungs expand and retract
    Hearing develops
    Fat layer develops under baby's skin
    By week 24, baby reaches viability, a high likelihood of surviving outside the womb
    Eyelids have formed and opened
    Baby can weigh about 2lbs
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    Third Trimester

    Organs continue to mature
    Baby develops sleep cycle
    Hair remains on eyebrows, head and eyelashes
    Bones continue to harden
    Most major organs can work on their own
    Baby moves to lower position, should be facing head-down
    Brain controls bodily functions including breathing
    Average baby weighs about 7lbs and measures 20 inches
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    Birth through 2 weeks

    If baby's head was cone shaped after birth, it should begin to return to normal
    Umbilical cord will dry and fall off
    Hands will clench involuntarily and baby will startle at loud noises
    Can recognize parents' voices
    Touch and talking can promote bonding
    Babies will cry at anything that makes them uncomfortable, from hunger to dirty diaper to separation anxiety
    Babies will form neural connections through their senses, particularly touch, sight, and hearing