Quick Answer
At 31 weeks, your baby is about the size of a coconut (~41cm, 1.5 kg). Baby’s brain is developing rapidly — processing information from all five senses now. You’ll notice distinct sleep and wake patterns. Your body is dealing with the weight — backaches, breathlessness, and Braxton Hicks contractions are all par for the course at this stage.
Baby Development at Week 31
Your baby’s nervous system is maturing fast. Here’s what’s happening:
- Brain development is accelerating — processing more information and stimuli from the environment
- All five senses are active — baby can see light, hear sounds, taste amniotic fluid, and respond to touch
- Distinct wake/sleep patterns — you’ll notice predictable active and quiet periods throughout the day
- Lungs continue to mature — surfactant production is increasing but lungs aren’t fully ready yet
- Fat is accumulating — baby is filling out, skin is less wrinkly
- Movements are more coordinated — you may feel stretching, rolling, and strong kicks
Baby’s irises can now react to light. If you shine a flashlight at your belly, baby might turn towards it.
Your Body at Week 31
The third trimester discomforts are in full swing now. Your uterus is about 11 cm above your belly button.
Common Symptoms
| Symptom | What’s Happening | What Helps |
|---|---|---|
| Shortness of breath | Uterus pushing diaphragm up, reducing lung space | Sit upright. Sleep propped up. It improves after baby drops |
| Backache | Extra weight + loosened ligaments (relaxin hormone) | Warm compress. Good posture. Avoid standing too long |
| Braxton Hicks contractions | Practice contractions — irregular, painless tightening | Change position. Drink water. They should stop with rest |
| Frequent urination | Baby’s head pressing on bladder | Don’t reduce fluids. Lean forward when peeing to empty fully |
| Swollen feet and ankles | Increased blood volume + fluid retention | Elevate legs. Avoid standing long. Reduce salt |
| Heartburn | Progesterone relaxes the valve between stomach and esophagus | Small meals. Don’t lie down right after eating. Avoid spicy food |
| Trouble sleeping | Combination of discomfort, bathroom trips, and baby’s kicks | Left side sleeping. Pregnancy pillow. Warm milk before bed |
Braxton Hicks vs Real Contractions
At 31 weeks, Braxton Hicks are normal. They’re your uterus practicing. Call your doctor if: contractions become regular (every 10 minutes or less), get stronger over time, or are accompanied by lower back pain, pelvic pressure, or watery discharge — these could be signs of preterm labor.
Tests & Screenings Due
You should be visiting your doctor every 2 weeks now (weeks 28-36).
At Your Fortnightly Visit
- Blood pressure check — watching for preeclampsia (BP ≥ 140/90 + proteinuria)
- Urine test — protein and sugar screening
- Fundal height measurement — should roughly match gestational age in cm
- Baby’s heartbeat — via Doppler
- Weight check — expected gain is about 0.5 kg/week in third trimester
Coming Up
- Growth scan at 32-34 weeks — to check baby’s size, amniotic fluid, and placenta position
- NST (Non-Stress Test) may start at 32+ weeks if you’re high-risk (gestational diabetes, hypertension, previous complications)
Nutrition This Week
You need about 460 extra calories per day in the third trimester (ICMR guideline). Focus on iron, calcium, and protein.
What to Prioritize
- Iron-rich foods — ragi, bajra, jaggery, green leafy vegetables, pomegranate. Anemia is common in third trimester
- Calcium — 1000 mg/day recommended. Milk, curd, paneer, ragi, sesame seeds (til)
- Protein — aim for 78g/day. Dal, chana, rajma, eggs, chicken, fish (well-cooked)
- Omega-3 fatty acids — for baby’s brain development. Walnuts, flaxseeds, fish oil (if prescribed)
- Fiber — constipation is very common now. Whole grains, fruits, salads, isabgol if needed
- Stay hydrated — 2.5-3 litres per day
What to Avoid
- Excess salt — worsens swelling
- Large meals — eat smaller, more frequent meals to manage heartburn
- Raw or undercooked food
- Caffeine — keep under 200 mg/day
When to Call Your Doctor
These symptoms need immediate attention in the third trimester:
- Regular contractions before 37 weeks — could be preterm labor
- Sudden swelling of face or hands with headache — possible preeclampsia
- Severe headache that doesn’t go away with visual changes (blurry vision, seeing spots)
- Vaginal bleeding — any amount
- Gush or trickle of fluid — could be amniotic fluid leak
- Baby not moving — fewer than 10 movements in 2 hours after eating and lying down
- Painful urination with fever — UTI risk increases in pregnancy
- BP ≥ 140/90 if you’re monitoring at home
Don’t hesitate. Better to go in and have everything be fine than to wait at home worrying.
What’s Coming Up
- Week 32: Growth scan recommended. Most organs are ready except lungs and brain. Skin becomes opaque
- Week 33: Bones are hardening — skull bones stay soft for the birth canal
- Weeks 32-34: If you’re high-risk, NST and biophysical profile monitoring may begin
Aapke Sawaal (Common Questions)
Kya 31 weeks mein baby ulta (breech) ho toh tension leni chahiye?
Abhi nahi. 31 weeks mein bahut se babies breech hote hain. Baby ke paas abhi palat-ne ki jagah hai. Zyaadatar babies 34-36 weeks tak apne aap head-down ho jaate hain. Agar 36 weeks tak nahi palte toh doctor ECV (External Cephalic Version) discuss karenge.
Raat ko neend nahi aati — kya karein?
Third trimester mein neend ka bigadna bahut common hai. Left side pe so-ein, pair ke beech pillow rakhein. Sone se pehle warm doodh peeyein. Screen time kam karein. Agar restless legs ho raha hai toh iron levels check karwa-ein.
Braxton Hicks aur real contractions mein fark kaise pata chalega?
Braxton Hicks irregular hote hain, position change karne se ruk jaate hain, aur pet ke aage feel hote hain. Real contractions regular hote hain, time ke saath strong hote hain, aur back se start hoke aage aate hain. Agar 10 minute mein ek baar aa rahe hain toh doctor ko call karein.
