At 31 weeks pregnant, you are well into your third trimester and the finish line is starting to feel real. Your baby is growing steadily, your body is working hard to accommodate them, and this is a lovely moment to focus on rest, connection and gentle preparation for birth. If you have just arrived from week 30, you will notice that the coming weeks are largely about your baby maturing and gaining weight rather than forming new features.
Here is what is typically happening for you and your baby around week 31, along with the appointments and checks that may be relevant now.
Your baby at week 31
By 31 weeks, your baby is roughly the size of a coconut or a large squash, measuring approximately 40 centimetres from head to heel and weighing somewhere in the region of 1.5 kilograms. These figures are general averages only, and healthy babies vary considerably in size.
Much of the important structural development is already complete, so this stage is largely about growth and maturation. Your baby is laying down fat beneath the skin, which helps smooth out their appearance and will support temperature regulation after birth. The lungs continue to mature, and the brain is developing rapidly, forming connections at a remarkable pace.
You may notice your baby has settled into more recognisable patterns of activity and rest. Movements often feel stronger and more defined now, with rolls, stretches and the occasional sharp kick under the ribs. Getting to know your baby's usual pattern of movement is one of the most valuable things you can do at this stage.
Your body at week 31
As your bump grows, you may find a range of third-trimester symptoms becoming more noticeable. These are common and usually a normal part of pregnancy, though everyone experiences them differently.
- Breathlessness, as your growing uterus presses upwards against your diaphragm.
- Backache and pelvic discomfort, as your posture shifts and pregnancy hormones soften your ligaments.
- Braxton Hicks contractions, which are irregular, usually painless tightenings that help your body prepare for labour.
- Swelling in the feet, ankles and hands, particularly later in the day.
- Broken sleep, heartburn, and more frequent trips to the loo as your baby presses on your bladder.
- Colostrum, the first milk, which some people begin to leak from their breasts around now.
Sudden or severe swelling, particularly of the face and hands, a bad headache, or visual disturbances are not typical and should be checked promptly, as they can be signs of a condition that needs assessment. If anything feels different or worrying, it is always worth contacting your midwife.
What to keep in mind this week
Monitoring your baby's movements remains important throughout the third trimester. Contrary to a common myth, babies do not move less towards the end of pregnancy. If you notice your baby's movements have slowed, stopped, or changed, contact your maternity unit straight away, at any time of day or night, so they can be checked.
This is also a sensible week to gently continue your practical preparations. You might think about packing your hospital bag, finalising your birth preferences, and resting whenever you can. Staying hydrated, eating regular balanced meals and keeping gently active, where comfortable, can all help you feel your best.
If you would like a personalised overview of what lies ahead, our pregnancy journey planner can map out the weeks to come alongside the scans and milestones that may matter for you.
Scans, tests and appointments
By 31 weeks, most of the routine NHS screening milestones are behind you. The 20-week anomaly scan takes place at around 18 to 21 weeks, and the glucose tolerance test for gestational diabetes, where offered, is typically carried out between 24 and 28 weeks.
Some vaccinations remain relevant now. The whooping cough vaccine is offered in each pregnancy and can be given up to around 32 weeks and beyond, while the RSV vaccine is recommended from 28 weeks to help protect your baby in their early months. Your midwife or GP can talk through the timing that applies to you. Discussions around group B streptococcus may also come up in the later part of the third trimester.
Alongside your NHS antenatal care, some parents choose additional reassurance at this stage. A private wellbeing scan can offer a detailed look at your baby's growth, position and the amniotic fluid, and can be particularly reassuring in the weeks before birth. If you are preparing mentally and emotionally for labour, our calm birthing course is designed to help you approach the birth with confidence and calm.
Looking ahead to week 32
As you move towards week 32, your baby will keep growing and gaining weight, and many babies begin to settle into a head-down position ready for birth in the coming weeks. Take each week as it comes, listen to your body, and lean on your midwifery team whenever you need support.
This article is for general information only and is not a substitute for professional medical advice. Always speak to your midwife, GP or obstetrician about your own pregnancy.
