20 weeks pregnant
You're halfway there.
In short
At 20 weeks your baby is about the size of a banana, around 25.7 cm long and 330 g. You're halfway there.
- Second trimester, week 20 of about 40.
- Some maternity units do the anatomy scan between 20 and 22 weeks.
Your baby's skin is covered in vernix, a white, greasy coating that protects it in the fluid. Sweat glands are forming under the skin.
How big is my baby at 20 weeks?
At 20 weeks your baby is about the size of a banana, around 25.7 cm long and 330 g. Before about 14 weeks babies are measured from crown to rump; after that the figure is head to heel. These are typical figures from fetal growth charts. Your own baby may be bigger or smaller, and your scans are what count.
What is my baby doing at 20 weeks?
- Your baby's skin is covered in vernix, a white, greasy coating that protects it in the fluid.
- Sweat glands are forming under the skin.
- Your baby now has times of being asleep and times of being awake.
- From about now, babies are usually measured from head to heel rather than head to bottom.
What changes for me at 20 weeks pregnant?
- Week 20 is usually the halfway point of pregnancy.
- Morning sickness has eased by now for most people.
- Cramp in your calves is common, especially at night. Pulling your toes up towards you or rubbing the muscle can help.
What is a good tip for this week?
There's no set number of movements to feel. Get to know your baby's pattern and contact your maternity unit straight away if movements slow down, change or stop.
What can a partner do this week?
Ask to feel for movements and chat to the bump, which can help you start to bond.
What should I know in Ireland at 20 weeks?
- Some maternity units do the anatomy scan between 20 and 22 weeks.
- From 20 weeks your checks will usually include feeling your bump and asking about your baby's movements.
When to get help: Contact your midwife, GP or maternity unit urgently if you get a bad headache, blurred vision or flashing lights, pain just below your ribs or sudden swelling of your face, hands or feet. HSE: when to get help.
Want these updates on your phone? The Lullagram app has a free pregnancy section with this week-by-week guide, Irish dates worked out from your due date, a contraction timer and more. When your baby arrives, the baby tracker is ready in the same app.
Sources and guidance
This page is written to be consistent with the official guidance below. It is general information for parents in Ireland, not medical advice. Links checked 23 September 2026.