Second Trimester

Pregnancy Week 18

Your baby is about the size of a bell pepper 🫑anatomy scan week (typically 18–20).

Week 17Week 18 / 40Week 19
🫑

Size comparison

Bell pepper

Length

14.2 cm

Weight

190 g

Milestone

Anatomy scan week (typically 18–20)

About 22 weeks to go until your due date (week 40).

Baby's development at week 18

The anatomy scan this week checks all major organs and can often reveal the sex. Your baby yawns, hiccups, and rolls. The ears are fully formed and can hear external sounds clearly.

Book your anatomy scan (morphology scan) at 18–20 weeks if not already scheduled.

Common symptoms at week 18

Back acheSwollen feet/anklesVivid dreams

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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