17 weeks pregnant
Unique fingerprints are in place.
In short
At 17 weeks your baby is about the size of a pear, around 20.4 cm long and 179 g. Unique fingerprints are in place.
- Second trimester, week 17 of about 40.
- The fetal anatomy scan is usually offered between 18 and 22 weeks, but timing depends on your hospital. If you don't have a date yet, ask your maternity unit.
Turn your baby round in 3D every week in the free Lullagram pregnancy section
Your baby's fingerprints have formed, each with its own unique pattern. Eyebrows and eyelashes are growing and the eyes can move behind closed lids.
How big is my baby at 17 weeks?
At 17 weeks your baby is about the size of a pear, around 20.4 cm long and 179 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 17 weeks?
- Your baby's fingerprints have formed, each with its own unique pattern.
- Eyebrows and eyelashes are growing and the eyes can move behind closed lids.
- Your baby can open and close their mouth and has a firm grip.
- Fingernails and toenails are growing.
What changes for me at 17 weeks pregnant?
- Your bump is becoming more noticeable as your womb rises out of your pelvis.
- You may notice stretch marks on your tummy, breasts or thighs. Most people get them and they usually fade after the birth.
- Feeling anxious from time to time is common and talking about it helps.
What is a good tip for this week?
Keeping your skin moisturised may ease any tightness or itch from stretch marks.
What can a partner do this week?
Offer a foot or back rub at the end of the day.
What should I know in Ireland at 17 weeks?
- The fetal anatomy scan is usually offered between 18 and 22 weeks, but timing depends on your hospital. If you don't have a date yet, ask your maternity unit.
When to get help: If back or pelvic pain becomes severe, talk to your midwife, GP or maternity unit. 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.
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