40 weeks pregnant
Your due date week.
In short
At 40 weeks your baby is about the size of a small pumpkin, around 51.0 cm long and 3.62 kg. Your due date week.
- Third trimester, week 40 of about 40.
- Ask your midwife what happens if you go past your due date. In a straightforward pregnancy you'll usually be offered an induction at 41 weeks.
Turn your baby round in 3D every week in the free Lullagram pregnancy section
Your baby is ready to be born. The lanugo hair is almost all gone.
How big is my baby at 40 weeks?
At 40 weeks your baby is about the size of a small pumpkin, around 51.0 cm long and 3.62 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 40 weeks?
- Your baby is ready to be born.
- The lanugo hair is almost all gone.
- Because of your hormones, your baby's genitals may look swollen at birth, which settles quickly.
- Your baby should still be moving in their usual pattern, even though space is tight.
What changes for me at 40 weeks pregnant?
- Pregnancy lasts about 40 weeks, but only around 5 in 100 babies arrive on their due date.
- Most women go into labour within 7 to 10 days of their due date.
- Feeling impatient or fed up is completely normal.
What is a good tip for this week?
Plan a few small things to look forward to each day so the waiting feels shorter.
What can a partner do this week?
Keep things calm at home and handle the messages from family asking for news.
What should I know in Ireland at 40 weeks?
- Ask your midwife what happens if you go past your due date. In a straightforward pregnancy you'll usually be offered an induction at 41 weeks.
When to get help: Your baby should not move less before birth, so if movements slow down, change or stop, contact your maternity unit straight away. 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.
Great app that has everything. great especially around the new born phase where you need to record and keep an eye on everything for doctors/nurses and your own self assurance. Quick action buttons help and although I haven't yet posted on it, the community section is brilliant for help and reassurance that I'm doing things right and that certain things that happen are normal and nothing to worry about.