First trimesterWeek 4 of 40
Your baby at 4 weeks pregnant
Your baby is the size of a poppy seed — about <0.1 in long and weighing approximately <0.1 oz.
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Poppy seed
The size of a poppy seed
Length (crown to heel)
<0.1 in
Approximate weight
<0.1 oz
Baby's hand
2mm
Baby's foot
2mm
Pregnancy progress0%
🌱 Baby's development at 4 weeks
A tiny cluster of cells, already with so much potential. Your body is quietly doing extraordinary things.
🤰 Your body at 4 weeks
You may not feel pregnant yet, but hormones are already surging. A missed period and early fatigue are often the first signs.
✨ Did you know?
Your baby is a bundle of about 150 cells called a blastocyst — already burrowing into your uterine lining to start its home for the next nine months.
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