12 weeks pregnant baby size
By Pregora Editorial Team · Updated 2026-05-07 · 3 min read
At 12 weeks pregnant, your baby is about 5.4 cm / 2.1 in long and weighs around 14 g / 0.5 oz — comparable in size to a lime. About the size of a lime — and you've nearly completed the first trimester.
Length
5.4 cm / 2.1 in
Weight
14 g / 0.5 oz
Size of
Lime
Week 12 milestones
- Reflexes are developing — baby can curl fingers and toes
- Vocal cords are forming
- External genitalia are starting to differentiate (boy vs girl)
- Risk of miscarriage drops significantly after week 12
Tip for week 12
Many couples announce their pregnancy after week 12 because the miscarriage risk drops to under 1% at this point.
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Disclaimer: Baby measurements are population averages — individual babies vary. Always consult your healthcare provider for personalised growth assessments based on your ultrasound scans.
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