you're 31 weeks pregnant.
last revised · baby is about 41.1 cm (16.2") · 1500 g (52.9 oz)
At 31 weeks pregnant, your baby is about 41.1 cm and 1500 g — Your baby's senses are nearly newborn-ready.
about the size of a…
Your baby's senses are nearly newborn-ready. They can hear, see, taste, and respond to touch through the belly.
this week's highlights
- All five senses functional
- Strong startle reflex
- Body length grows fast
- Pupils dilate to light
how your baby looks
Plump and pink. Hair on head is thicker, vernix is still protecting the skin, and limbs are fully proportioned.
body in focus
- head
- Pupils dilate and contract; all senses functional.
- body
- Body length is growing faster than weight.
- hands
- Hands are well-coordinated for sucking and grasping.
- feet
- Strong kicks and stretches feel like ripples.
what's happening in your body
Bump is heavy now. You may feel pelvic pressure, frequent peeing, and occasional Braxton-Hicks. Sleep stays unreliable.
symptoms at 31 weeks
- Pelvic pressure
- A heavy, dragging feeling low in the pelvis comes from the baby's weight and loosened joints. Rest breaks off your feet, a support belt, and pool sessions all take the load off.
- Breathless in conversation
- You may find yourself pausing mid-sentence as lung space shrinks. Slowing down is normal; breathlessness at rest, with palpitations or chest pain, needs urgent medical advice.
- Leaking urine vs waters
- Small bladder leaks with movement are common and different from waters breaking. If fluid keeps trickling regardless of activity or smells sweet rather than of urine, put on a pad and call your maternity unit.
- Braxton Hicks with position changes
- Tightenings triggered by standing up or rolling over are typical now. Note their pattern — irregular and settling is fine; regular and building is a call to your midwife.
- Overheating and night sweats
- Extra blood volume and metabolism run you warm. Layered bedding, a fan, and cotton nightwear beat one heavy duvet.
- Aching wrists and ankles
- Fluid retention peaks in the extremities late in the day. Elevation, gentle rotation exercises, and compression socks worn from the morning all help.
gentle tips
- Practice positions for labor (squatting, leaning forward, hands-knees).
- Get a perineal-massage routine going if recommended.
- Rest with feet up multiple times a day.
- Take birth and breastfeeding classes if not yet completed.
- Discuss when to call your provider during labor.
your week 31 checklist
- Practise your route to the maternity unit at different times of day, including where to park and which entrance to use at night.
- Discuss pain relief options for labour at your next appointment so choices are made calmly, not mid-contraction.
- Prepare a one-page contact-and-logistics sheet: triage number, hospital address, who looks after pets or older children.
- Continue daily movement awareness — any reduction means contacting your maternity unit immediately.
what to expect next
Prenatal visits become more frequent. Birth feels closer — most babies turn head-down between now and week 36.
common questions at week 31
How big is the baby at 31 weeks?
At 31 weeks, the baby measures about 41.1 cm and weighs approximately 1500 g (41.1 cm (16.2") · 1500 g (52.9 oz)).
What is developing at 31 weeks?
Plump and pink. Pupils dilate and contract; all senses functional. Key milestones this week include: All five senses functional; Strong startle reflex; Body length grows fast; Pupils dilate to light.
What symptoms are common at 31 weeks pregnant?
Bump is heavy now. You may feel pelvic pressure, frequent peeing, and occasional Braxton-Hicks. Sleep stays unreliable.
What should I do at 31 weeks pregnant?
Prenatal visits become more frequent. Practice positions for labor (squatting, leaning forward, hands-knees). Get a perineal-massage routine going if recommended. Rest with feet up multiple times a day.
How do I know if it is my waters leaking or just urine?
Urine leaks happen in spurts with coughing, laughing, or movement, smell of ammonia, and stop; amniotic fluid tends to keep trickling regardless of activity, is usually clear or pale straw-coloured, and smells sweetish or of nothing. If in doubt, put on a clean pad, lie down for half an hour, and see if fluid pools when you stand — then call your maternity unit to describe it. They would always rather assess than have you wait.
Why do I get short of breath just talking at 31 weeks?
Your uterus now pushes the diaphragm several centimetres higher than usual, reducing how deeply your lungs can expand, while pregnancy also increases how much air you need to move. Feeling puffed during conversation or mild activity is expected and improves once the baby engages lower in the pelvis. Sudden severe breathlessness, chest pain, or breathlessness with a racing heart is different — seek urgent medical help for that.
Are frequent baby hiccups in the womb normal?
Yes — rhythmic little jumps that last a few minutes are hiccups, a normal part of your baby practising breathing movements, and some babies hiccup several times a day. They generally are not counted as movements for pattern-tracking purposes, so keep noticing kicks, rolls, and stretches separately. If hiccups suddenly become constant and frantic alongside reduced normal movement, contact your maternity unit.
helpful tools
- Kick Counter
Daily kick counts are an important reassurance in the third trimester.
- Contraction Timer
Time contractions and track frequency when the moment comes.
- Hospital Bag
Curated packing checklist for labor and delivery.
Medically aligned with guidance from WHO, NHS and ACOG. How we write.