Pregnancy Week 31: What to Expect
Baby's development, your body's changes, common symptoms, what to eat, and what to do this week.
Baby's development at week 31
Baby gains ~1/2 to 1 lb per week from now. Baby's skin smoothens as fat fills in under it. Baby's central nervous system matures. Baby's lungs continue maturing — production of surfactant ramps up significantly. Baby's eyes can dilate and constrict in response to light. Baby has clear circadian rhythms now, though they will not align with yours postpartum for months.
What's happening in your body
Your uterus is about 4.5 inches above the belly button. Frequent Braxton Hicks contractions. Lower back pain common. Sleep is very short — frequent pee breaks, baby movements, discomfort. Possible mild shortness of breath. Possible Braxton Hicks contractions. Possible mild swelling.
Common symptoms at week 31
Frequent Braxton Hicks. Lower back pain. Short sleep. Possible mild breathlessness. Strong fetal movements. Possible swelling. Possible heartburn. Possible mild dizziness.
When to call your provider
Watery discharge or trickle (could be amniotic fluid leak) — call provider. Painful regular contractions, bleeding, severe headache/vision changes, severe swelling — same.
How to feel better this week
Have the hospital bag fully packed and ready by next week. Include: comfortable clothing, toiletries, phone charger, snacks, water bottle, baby's coming-home outfit, car seat installed. Continue Kegels. Side sleeping. Walks. Hydrate. Apply lotion.
Nutrition focus for week 31
Continue iron, calcium, protein, healthy fats, fiber. Add foods rich in magnesium (nuts, seeds, dark chocolate, leafy greens) for leg cramps and sleep. Stay hydrated; dehydration triggers Braxton Hicks.
For your partner
Finalize hospital bag. Drive route to hospital at different times of day. Plan for who will look after older kids/pets when labor starts.
This week's to-do
Pack/finalize hospital bag. Plan for kids/pets during labor.
Is this normal?
Babies born at 32 weeks have ~95% survival without major issues. Each week past 30 dramatically improves outcomes. The baby growing inside is becoming more and more "ready."
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