Pregnancy (month by month)

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    The First Month

    Size at 2 weeks: size of a pin head
    Egg attaches to lining of uterus
    Critical stage for brain and spinal cord development
    Internal organs and circulatory system begin to form
    The heart begins to beat
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    The Second Month

    Size: About 1/4 an inch long as month begins
    Face, ears, eyes, and limbs begin to take shape
    Bones begin to form
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    The Third Month

    Size: About one inch long as month begins
    Nostrils, mouth, lips, and eyelids form
    Buds for all 20 baby teeth appear
    Fingers and toes almost complete
    All organs present but still immature.
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    The Fourth Month

    Size: About 3 inches long, weighs one ounce as month begins
    Can suck its thumb, swallow, hiccup, and move around
    Facial features become clearer
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    The Fifth Month

    Size: About 6 1/2 to 7 inches long, weighs about 4-5 ounces as month begins
    Hair, eyelashes, and eyebrows appear
    Teeth continue to develop
    Organs are maturing
    Becomes more active
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    The Sixth Month

    Size: About 8-10 inches long, weighs about 8-12 ounces as month begins
    Fat deposits under skin, but fetus appears wrinkled
    Breathing movements begin
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    The Seventh Month

    Size: About 10-12 inches long, weighs about 1 1/2 to 2 pounds as month begins
    Has periods of activity followed by periods of rest and quiet
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    The Eighth Month

    Size: About 14-16 inches long, weighs about 2 1/2 to 3 pounds as month begins
    Rapid weight gain continues
    May react to loud noises with a reflex jerking action
    Moves into a head-down position
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    The Ninth Month

    Size: About 17-18 inches long, weighs 5-6 pounds as month begins
    Weight gain continues
    Skin becomes smooth as fat deposits continue
    Movements decrease as the fetus has less room to move around
    Acquires disease-fighting antibodies from the mother's blood
    Descends into pelvis, ready for birth