40 weeks pregnant baby size
By Pregora Editorial Team · Updated 2026-05-07 · 3 min read
At 40 weeks pregnant, your baby is about 51.2 cm / 20.2 in long and weighs around 3.4 kg / 7.5 lb — comparable in size to a small pumpkin. About the size of a small pumpkin — and officially full term.
Length
51.2 cm / 20.2 in
Weight
3.4 kg / 7.5 lb
Size of
Small pumpkin
Week 40 milestones
- Vernix (waxy coating) covers the skin — protects in amniotic fluid
- Baby's grip reflex is strong enough to grasp a finger
- Bone marrow is producing red blood cells
- Lungs are fully mature and ready for first breath
Tip for week 40
Only ~5% of babies are born exactly on the due date. Most arrive between 38-42 weeks. Stay patient and trust your body.
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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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