Second Trimester

Pregnancy Week 21

Your baby is about the size of a carrot 🥕taste buds working.

Week 20Week 21 / 40Week 22
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Size comparison

Carrot

Length

26.7 cm

Weight

360 g

Milestone

Taste buds working

About 19 weeks to go until your due date (week 40).

Baby's development at week 21

Taste buds are fully formed and your baby can taste the amniotic fluid — flavours from your diet pass through. Research shows babies show preference for foods mum ate during pregnancy.

Eat a variety of vegetables — your baby is already developing food preferences!

Common symptoms at week 21

Braxton Hicks contractions may beginLeg crampsBack pain

Eat more of

  • Omega-3 fatty acids (salmon, flaxseed)
  • Calcium & Vitamin D (cheese, eggs, sunlight)
  • Protein (chicken, legumes, eggs)
  • Iron + Vitamin C together for absorption
  • Magnesium-rich foods (nuts, seeds, dark chocolate)

Foods to avoid

  • Alcohol
  • Raw/smoked seafood
  • High-mercury fish
  • Unpasteurised cheeses (brie, camembert)
  • Processed meats (deli cuts, hot dogs)
  • Excess sugar

Medically reviewed by First OPD Medical Team. Last reviewed on .

Based on average milestones from World Health Organization (WHO), ACOG, NHS UK. Educational only — not a substitute for personalised medical advice.

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