Science Gallery

See how you grew from a tiny speck to a full-sized baby

Size Comparisons

Everyday objects help you visualize how tiny you once were

Day 0Hello, First Cell~0.1 mm

Wk 1Snuggling In~0.15 mm

Wk 3A Heart That Starts Young~2 mm · <0.02 g

Wk 5A Brain Takes Shape~4 mm · <0.1 g

Wk 6Electric Whispers~8 mm · ~0.1 g

Wk 8Blueprint for Every Organ~3 cm · ~3 g

Wk 9Little Movements, Big Meaning~4 cm · ~7 g

Wk 10Ridges That Never Repeat~5 cm · ~14 g

Wk 12Stretch, Yawn, Practice~9 cm · ~45 g

Wk 16Ears Tuning In~14 cm · ~200 g

Wk 20Midway Mark~25 cm · ~350 g

Wk 24Sound and Flavor~35 cm · ~760 g

Wk 28Light Reaches In~40 cm · ~1.3 kg

Wk 32Sleep With a Story~45 cm · ~2.1 kg

Wk 38Ready to Meet the World~51 cm · ~3.4 kg

Discover how different parts of your body grew

Your heart started beating just 3 weeks after you began, pumping blood throughout your body.

Wk 3Wk 8

Your brain started building connections that would help you think, feel, and dream.

Wk 5Wk 6Wk 32

You could wiggle, kick, make a fist, and even get the hiccups!

Wk 9Wk 12Wk 20

You could hear your mom's voice, see light, and even taste the food she ate!

Wk 16Wk 24Wk 28

Your lungs practiced breathing movements to get ready for your first breath of air.

Wk 8Wk 20Wk 38