Week 1 of Pregnancy
First trimester
Baby is
smaller than a poppy seed
0.1 mm · less than 1 oz
Baby this week
- •Conception has just occurred - sperm and egg have merged to form a zygote
- •Cell division begins immediately as your baby starts the journey to becoming an embryo
- •Genetic material from both parents combines to determine your baby's traits
You this week
- •You may not feel any different yet - that's completely normal
- •Some people experience implantation symptoms in the coming days (light spotting, mild cramping)
- •Hormonal shifts are beginning but may not be noticeable
This week's tips
- •Start taking prenatal vitamins with folic acid if you haven't already - this supports early neural development
- •Keep track of your cycle to confirm pregnancy timing when you test
- •Continue healthy habits: balanced nutrition, staying hydrated, and managing stress
- •Avoid alcohol, smoking, and recreational drugs from this point forward
Looking ahead
Over the next week, your fertilized egg will travel down the fallopian tube and begin implanting into your uterine lining. By the end of week 2, you may be able to detect pregnancy with a sensitive test.
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