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🤰 Second trimester

20 weeks pregnant

Your baby is about the size of a banana

EW

By Emma Whitfield · Pregnancy & Baby Writer

Your baby at 20 weeks

You're halfway there. From now, length is measured head-to-heel. The baby is swallowing amniotic fluid and producing meconium (first poo). They have regular sleep-wake cycles.

Your body at 20 weeks

Most people have a clear bump by now and many feel regular movements. This is often when the anomaly scan happens. You might feel more energetic and comfortable.

Common symptoms this week

  • Clear, established bump
  • Regular noticeable movements
  • Feeling more comfortable than either end of pregnancy

Symptom lists are typical, never exhaustive — and having none of them is normal too.

Focus this week

After the 20-week scan is a good time to start researching big purchases — pushchair, car seat and cot have the longest lead times.

Week 20 checklist

  • Attend the anomaly scan — a detailed development check of heart, brain, spine, limbs and placenta position
  • Ask for your MATB1 certificate from around now — it unlocks maternity pay
  • Start researching the big purchases (pushchair, car seat, cot)

20 weeks pregnant: common questions

What does the 20-week anomaly scan check?

A detailed structural check of the baby — brain, face, spine, heart, stomach, kidneys, limbs — plus the placenta's position and amniotic fluid. Most scans are reassuring; if anything needs a closer look you'll be referred to a specialist, usually within days.

How big is my baby at 20 weeks pregnant?

At 20 weeks, your baby is approximately the size of a banana, about 25.6cm and around 300g. These are approximate averages — every baby grows at its own pace.

What's happening at 20 weeks pregnant?

You're halfway there. From now, length is measured head-to-heel. The baby is swallowing amniotic fluid and producing meconium (first poo). They have regular sleep-wake cycles. For you: most people have a clear bump by now and many feel regular movements. this is often when the anomaly scan happens. you might feel more energetic and comfortable.

Which trimester is 20 weeks?

20 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.