28 weeks pregnant
Welcome to the third trimester.
In short
At 28 weeks your baby is about the size of a coconut, around 37.9 cm long and 1.19 kg. Welcome to the third trimester.
- Third trimester, week 28 of about 40.
- If your blood group is rhesus negative, you'll usually be offered an anti-D injection at 28 weeks. Some hospitals can first check whether your baby is rhesus negative, in which case you won't need it.
Turn your baby round in 3D every week in the free Lullagram pregnancy section
Your baby is putting on fat and looking less wrinkled. Their heart beats about 140 times a minute, much faster than yours.
How big is my baby at 28 weeks?
At 28 weeks your baby is about the size of a coconut, around 37.9 cm long and 1.19 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 28 weeks?
- Your baby is putting on fat and looking less wrinkled.
- Their heart beats about 140 times a minute, much faster than yours.
- Your baby can open and close their eyes.
- Your baby moves in response to your voice and touch.
What changes for me at 28 weeks pregnant?
- Your antenatal appointments will become more frequent from now on.
- Heartburn and backache are common as your baby grows.
- Going to sleep on your side rather than on your back is safer for your baby in later pregnancy.
What is a good tip for this week?
Tuck a pillow under your bump and another between your knees to help you settle on your side. If you wake on your back, just turn over.
What can a partner do this week?
Help set up extra pillows at bedtime to make side sleeping more comfortable.
What should I know in Ireland at 28 weeks?
- If your blood group is rhesus negative, you'll usually be offered an anti-D injection at 28 weeks. Some hospitals can first check whether your baby is rhesus negative, in which case you won't need it.
- From 28 weeks your checks will look at your baby's growth and position and your blood pressure.
When to get help: If your baby's movements slow down, change or stop, contact your maternity unit straight away and don't use a home doppler or app to check. 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.