For the full version: http://www.mayoclinic.com/health/prenatal-care/PR00112

Fetal development begins soon after conception. Find out how your baby grows and develops during the first trimester.
By Mayo Clinic staff

You're pregnant. Congratulations! You'll undoubtedly spend the months ahead wondering how your baby is growing and developing. What does your baby look like? How big is he or she? When will you feel the first kick?

Fetal development typically follows a predictable course.
Find out what happens during your baby's first three months in the womb by checking out this weekly calendar of events.

Weeks 1 and 2: Getting ready

It may seem strange, but you're not actually pregnant the first week or two of the time allotted to your pregnancy. Yes, you read that correctly!

Conception typically occurs about two weeks after your period begins. To calculate your due date, your health care provider will count ahead 40 weeks from the start of your last period. This means your period is counted as part of your pregnancy — even though you weren't pregnant at the time...