Title: Early Pregnancy Fetal Development
Headings: Early Pregnancy Fetal Development
Early Pregnancy Fetal Development
Early Pregnancy
4 Weeks of Pregnancy
7 Week Embryo
8 Week Fetus
10 Week Fetus
12 Week Fetus
16 Week Fetus
24 Week Fetus
26-28 Week Fetus
30-39 Week Fetus

Content: 6 ﻿ By now, the fetal brain weighs an impressive 43 percent of the total mass of the fetus. This week the baby's gonads will become either testes or ovaries. 9 ﻿ The baby's fingers and toes are webbed and spontaneous movement begins! There are a lot of things that we do know about life before birth. All major organs have begun to form by the end of the eighth week. 10 ﻿
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10 Week Fetus
Photo © Science Picture Co/Getty Images
At the start of the tenth week, the average size of the fetus is approximately 3.2 centimeters CRL 6 ﻿ and weighs about four grams. 11 ﻿ Tiny toes formed in the ninth week, and now toenails and fingernails are growing. The eyelids have fused shut and will stay that way until they separate at around 28 weeks. 12 ﻿ External ears are continuing to develop, as well as the upper lip. External genitalia is beginning to differentiate.