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🤰 Second trimester

25 weeks pregnant

Your baby is about the size of a swede

EW

By Emma Whitfield · Pregnancy & Baby Writer

Your baby at 25 weeks

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.

Your body at 25 weeks

Some experience piles (haemorrhoids), restless legs or trouble sleeping. Your growing bump can make finding a comfortable position harder — a pregnancy pillow can help.

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.

Focus this week

Start thinking about your birth preferences, but keep them flexible. Discuss options with your midwife rather than fixing on one plan.

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

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 July 2026.