Second Trimester

Pregnancy Week 17

Your baby is about the size of a pear 🍐fat accumulating under skin.

Week 16Week 17 / 40Week 18
🍐

Size comparison

Pear

Length

13 cm

Weight

140 g

Milestone

Fat accumulating under skin

About 23 weeks to go until your due date (week 40).

Baby's development at week 17

The baby begins storing body fat, which will keep them warm and provide energy after birth. The skeleton is changing from soft cartilage to bone. Sweat glands are forming.

Sleep on your left side from now on to optimise blood flow to the placenta.

Common symptoms at week 17

Nasal congestionHeartburnOccasional dizziness

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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