Week 4 of Pregnancy

Pregnancy Calendar: You are now 4 weeks pregnant

4 weeks old fetus (baby)

Week 4 of fetal development

This week the simple ball of cells starts to transform into an embryo. The pregnant cells secrete a hormone called human chorionic gonadotrophins (hCG), and it is the presence of hCG in the blood or urine, which will confirm your pregnancy.

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