Week 1 of Pregnancy
First trimester
For informational purposes only. This page is not medical advice. Every pregnancy is different — always consult your doctor, midwife, or healthcare provider for guidance specific to your situation. In an emergency, call your provider or 911 immediately.
Baby is
about the size of a poppy seed
0.1 inches · less than 1 gram
Baby this week
- •Conception has just occurred - sperm and egg have merged to form a zygote
- •Cell division begins immediately, creating a cluster of identical cells
- •Your baby's genetic makeup is now complete, including sex and inherited traits
You this week
- •You may not notice any symptoms yet - that's completely normal
- •Possible light spotting if implantation hasn't occurred yet
- •Tender breasts in some cases
- •Mild cramping or pelvic sensations
This week's tips
- •Start taking prenatal vitamins with folic acid if you haven't already - this supports neural tube development
- •Continue healthy habits: balanced nutrition, regular movement, and adequate sleep
- •Limit caffeine intake (under 200mg daily is generally considered safe)
- •Avoid smoking, alcohol, and recreational drugs
- •Schedule your first prenatal appointment when you get a positive pregnancy test
Informational only — always check with your doctor or midwife for advice specific to you and your baby.
Looking ahead
Over the next week, the fertilized egg will travel through your fallopian tube toward your uterus, and implantation will occur—this is when your pregnancy officially takes hold. Hormones will soon begin ramping up, and a positive test should be possible in the coming days.
Track your pregnancy on BringBaby
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For informational purposes only. This page is not medical advice. Every pregnancy is different — always consult your doctor, midwife, or healthcare provider for guidance specific to your situation. In an emergency, call your provider or 911 immediately.
This content is for informational purposes only and is not medical advice. Every pregnancy and baby is different. Always consult your doctor, midwife, or pediatrician for guidance specific to your situation.
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