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Your Developing Baby in First Trimester: Weeks 1 - 12

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At four weeks:

- Your baby's brain and spinal cord have begun to form.

- The heart begins to form.

- Arm and leg buds appear.

- Your baby is now an embryo and one-twenty-fifth inch long.

At eight weeks:

- All major organs and external body structures have begun to form.

- Your baby's heart beats with a regular rhythm.

- The arms and legs grow longer, and fingers and toes have begun to form.

- The sex organs begin to form.

- The eyes have moved forward on the face and eyelids have formed.

- The umbilical cord is clearly visible.

- At the end of eight weeks, your baby is a fetus and looks more like a human. Your baby is nearly 1 inch long and weighs less than one-eighth ounce.

At 12 weeks:

- The nerves and muscles begin to work together. Your baby can make a fist.

- The external sex organs show if your baby is a boy or girl. A woman who has an ultrasound in the second trimester or later might be able to find out the baby's sex.

- Eyelids close to protect the developing eyes. They will not open again until the 28th week.

- Head growth has slowed, and your baby is much longer. Now, at about 3 inches long, your baby weighs almost an ounce.

For more resources on pregnancy click here.

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EmpowHER Guest

The first trimester is crucial for a pregnant lady, because they are high chances of miscarriage during this period.

November 14, 2012 - 1:20am
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