38 weeks pregnant
Your baby is getting into position.
In short
At 38 weeks your baby is about the size of a bag of potatoes, around 49.2 cm long and 3.19 kg. Your baby is getting into position.
- Third trimester, week 38 of about 40.
- Your maternity leave must start at least 2 weeks before the end of the week your baby is due, so it begins by around now if you're still working.
Turn your baby round in 3D every week in the free Lullagram pregnancy section
Your baby's heart and circulation are fully formed. In these last weeks your baby's head should move down into your pelvis, though sometimes this only happens once labour starts.
How big is my baby at 38 weeks?
At 38 weeks your baby is about the size of a bag of potatoes, around 49.2 cm long and 3.19 kg. 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 38 weeks?
- Your baby's heart and circulation are fully formed.
- In these last weeks your baby's head should move down into your pelvis, though sometimes this only happens once labour starts.
- Most of the fine lanugo hair has gone, though some babies are born with a few patches.
- Your baby keeps storing meconium, which usually comes out as their first poo after birth.
What changes for me at 38 weeks pregnant?
- You may see your bump drop lower as your baby moves down.
- More pressure in your pelvis and more trips to the loo are common.
- Your midwife will talk with you about getting ready for the birth.
What is a good tip for this week?
Time 3 contractions in a row with your phone or a watch. Call your midwife or maternity unit when they are regular, last at least 60 seconds and come every 5 minutes.
What can a partner do this week?
Learn how to time contractions so you can keep track when labour starts.
What should I know in Ireland at 38 weeks?
- Your maternity leave must start at least 2 weeks before the end of the week your baby is due, so it begins by around now if you're still working.
When to get help: Phone your maternity unit and go in if your contractions are 5 minutes apart and getting stronger, your waters break, you have bleeding or your baby's movements change. 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.
Guides for your pregnancy: pregnancy care in Ireland · maternity leave and benefit · hospital bag checklist · popular baby names · free IVF in Ireland · due date calculator
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.
I must say Lullagram has been a huge help in the house for the simple things. As most parents do, we take shifts at night and knowing what the baby drank and at what time helps during changeover. We both have access to the same account so I can see what my partner logged on the last feed without having to wake her. It also keeps track of everything for the PHN who thinks it's a great idea. There's loads of extras on it so it's definitely worth a punt.