Articles
Fetal development: The first trimester
Week 5: Hormone levels increase
Week 7: Baby's head develops
Week 8: Baby's nose forms
Week 9: Baby's toes appear
Week 10: Baby's elbows bend
Week 11: Baby's genitals develop
Week 12: Baby's fingernails form
Content
Weeks 1 and 2: Getting ready
Week 3: Fertilization
Week 4: Implantation
Week 5: Hormone levels rise
Week 6: The neural tube closes
Week 7: The head develops
Week 8: The nose forms
Week 9: Toes appear
Week 10: The elbows bend
Week 11: Genitals develop
Week 12: Fingernails form
Week 7: Baby's head develops
Week 8: Baby's nose forms
Week 9: Baby's toes appear
Week 10: Baby's elbows bend
Week 11: Baby's genitals develop
Week 12: Baby's fingernails form
Content
Weeks 1 and 2: Getting ready
Week 3: Fertilization
Week 4: Implantation
Week 5: Hormone levels rise
Week 6: The neural tube closes
Week 7: The head develops
Week 8: The nose forms
Week 9: Toes appear
Week 10: The elbows bend
Week 11: Genitals develop
Week 12: Fingernails form
Weeks 1 and 2: Getting ready
It might seem odd, but you're actually not pregnant the first week or two of what's counted as your pregnancy's 40 weeks. Conception typically happens about two weeks after the last period begins. But to find your estimated due date, your healthcare professional counts ahead 40 weeks from the start of your last period. That means the period is counted as part of your pregnancy timeline even though you weren't pregnant at the time.
