Second trimester
25 weeks pregnant
Your baby is about the size of a swede
By Clever Mum Parenting · Parenting guides
How big is the baby at 25 weeks pregnant?
At 25 weeks pregnant, your baby is about the size of a swede, roughly 34.6cm and around 660g. The baby is putting on baby fat, so their skin looks less wrinkled. They're developing more hair, and the nostrils begin to open, practising breathing movements. These are typical averages — your midwife's measurements are the ones that matter for your pregnancy.
What might you feel at 25 weeks?
Most people at 25 weeks notice some mix of the symptoms below — and plenty notice none of them. Some experience piles (haemorrhoids), restless legs or trouble sleeping. Your growing bump can make finding a comfortable position harder — a pregnancy pillow can help. None of this is a diagnosis; contact your midwife if something worries you.
Common symptoms this week
- Piles or restless legs for some
- Trouble finding a comfy sleep position
- Vivid dreams
Symptom lists are typical, never exhaustive — and having none of them is normal too.
What should you do at 25 weeks pregnant?
The useful job this week is practical, not medical. Start thinking about your birth preferences, but keep them flexible. Discuss options with your midwife rather than fixing on one plan. Pair it with the NHS week-by-week guide if you want a second description of the same stage.
Week 25 checklist
- Attend the 25-week appointment if this is your first baby — bump measurement, blood pressure, urine
- Try a pregnancy pillow before buying more gadgets — it's the one that earns its space
What else is useful at 25 weeks?
Use the week page for size and symptoms; use the guides below for the decisions that actually sit in this window — pay, packing, car seats, labour signs.
25 weeks pregnant: common questions
Why is my bump measured at appointments?
The tape measurement (symphysis-fundal height) tracks the womb's growth against your week of pregnancy and is plotted on a chart in your notes. It's a screening tool — measuring consistently small or large simply triggers a growth scan for a closer look, and most of those scans are reassuring.
How big is my baby at 25 weeks pregnant?
At 25 weeks, your baby is approximately the size of a swede, about 34.6cm and around 660g. These are approximate averages — every baby grows at its own pace.
What's happening at 25 weeks pregnant?
The baby is putting on baby fat, so their skin looks less wrinkled. They're developing more hair, and the nostrils begin to open, practising breathing movements. For you: some experience piles (haemorrhoids), restless legs or trouble sleeping. your growing bump can make finding a comfortable position harder — a pregnancy pillow can help.
Which trimester is 25 weeks?
25 weeks pregnant is in the second trimester. The first trimester runs to the end of week 12, the second from weeks 13 to 26, and the third from week 27 to birth.
Sources & further reading
This is general information, not medical advice — every pregnancy is different. For anything that worries you, and for all your antenatal care, speak to your midwife or GP. If your baby's movements ever slow down or change, contact your maternity unit immediately, day or night. Reviewed August 2026.