Title: Fetal development: The 1st trimester - Mayo Clinic
Headings: 
Fetal development: The 1st trimester
Weeks 1 and 2: Getting ready
Week 3: Fertilization
Week 4: Implantation
Week 5: Hormone levels increase
Week 6: The neural tube closes
Week 7: Baby's head develops
Week 8: Baby's nose forms
Week 9: Baby's toes appear
Week 10: Baby's elbows bend
Week 11: Baby's genitals develop
Week 12: Baby's fingernails form
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Content: Baby's head develops
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Fetal development five weeks after conception
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Fetal development five weeks after conception
Fetal development five weeks after conception
By the end of the seventh week of pregnancy — five weeks after conception — your baby's brain and face are the focus of development. Seven weeks into your pregnancy, or five weeks after conception, your baby's brain and face are growing. Depressions that will give rise to nostrils become visible, and the beginnings of the retinas form. Lower limb buds that will become legs appear and the arm buds that sprouted last week now take on the shape of paddles. Week 8: Baby's nose forms
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Fetal development six weeks after conception
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Fetal development six weeks after conception
Fetal development six weeks after conception
By the end of the eighth week of pregnancy — six weeks after conception — your baby might be about 1/2 inch (11 to 14 millimeters) long. Eight weeks into your pregnancy, or six weeks after conception, your baby's lower limb buds take on the shape of paddles. Fingers have begun to form. Small swellings outlining the future shell-shaped parts of your baby's ears develop and the eyes become obvious. The upper lip and nose have formed.