Your Baby: Week 4

fetal development

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Your body produces a hormone, hCG, which stops menstruation.

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A blastocyst forms and burrows into the lining; implantation is complete!

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It may take up to 4 days after fertilization before the egg implants.

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If the egg is not fertilized, you will eventually get your period.

WebMD Medical Reference Reviewed by Traci C. Johnson, MD on June 04, 2016
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