Third Trimester
Pregnancy Week 31
Your baby is about the size of a coconut 🥥 — rapid weight gain begins.
🥥
Size comparison
≈ Coconut
Length
41.1 cm
Weight
1.5 kg
Milestone
Rapid weight gain begins
About 9 weeks to go until your due date (week 40).
Baby's development at week 31
From now until birth, your baby will gain about 500g per week. The immune system is receiving maternal antibodies. The baby may be in head-down position already — feel for a hard round shape at the top of your bump.
Tour your birth centre or hospital labour ward if you haven't yet.
Common symptoms at week 31
Back painWaddlingShortness of breath (baby pressing on diaphragm)
Eat more of
- ✓Calcium & Vitamin K (broccoli, kale)
- ✓DHA-rich fish (sardines, salmon — cooked)
- ✓Iron-rich foods to prevent anaemia
- ✓Fibre-rich foods to combat constipation
- ✓Small frequent meals to ease heartburn
- ✓Dates (studies suggest easier labour)
Foods to avoid
- ✕Alcohol
- ✕Gas-producing foods (beans, cabbage) if uncomfortable
- ✕Very spicy food if causing heartburn
- ✕Raw/undercooked meat
- ✕High-sodium processed food
- ✕Large meals that worsen reflux
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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