36 weeks pregnant baby size
By Pregora Editorial Team · Updated 2026-05-07 · 3 min read
At 36 weeks pregnant, your baby is about 47.4 cm / 18.7 in long and weighs around 2.6 kg / 5.7 lb — comparable in size to a romaine lettuce. About the length of romaine lettuce — and almost ready for the world.
Length
47.4 cm / 18.7 in
Weight
2.6 kg / 5.7 lb
Size of
Romaine lettuce
Week 36 milestones
- Baby is officially 'late preterm' — most babies born now do well
- Lungs are nearly fully mature — surfactant production is robust
- Baby is gaining weight rapidly (about 1 oz per day)
- Head usually engages in the pelvis — 'lightening' begins
Tip for week 36
Group B Strep (GBS) test typically happens between weeks 35-37. If positive, you'll get IV antibiotics during labour.
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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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