The first trimester.

The first trimester includes the period from week 1 to week 12 – about the first three months of pregnancy. It’s the period of early fetal development, which starts when the egg is fertilized by a sperm cell.

Although you probably won’t be visibly pregnant, the first trimester is a time of incredible transformation. Knowing what changes to expect can prepare you for the months ahead with a positive, healthy attitude.

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