Trimester 3
Week 31
Your baby is about the size of a pineapple.
Length: 41.1 cm · Weight: 1500 g
Common this week: Shortness of breath, Braxton Hicks, Back pain, Rib pain, Insomnia, Swelling.
Baby development
- All five senses are working — the baby can see, hear, smell, taste, and feel.
- The baby practises breathing movements for about 30–40% of the time.
- The brain and nervous system continue to mature rapidly.
- The baby is putting on about 250 g per week from now.
Changes for you
- Braxton Hicks may become more frequent and stronger.
- Your belly button may be fully inverted.
- You might feel short of breath even when resting.
- Sleeping comfortably is challenging — a full pregnancy pillow can help enormously.
Tips
- Pack your hospital bag this week if not done.
- Know the signs of preterm labour: regular contractions, back pain, pelvic pressure, any fluid leaking.
- Practice relaxation and breathing techniques for labour.
- Eat iron-rich foods to support your blood levels.
Appointments
- Routine antenatal check.
- Anti-D for Rh-negative women may be due at 34 weeks — confirm with your doctor.
Warning signs
- Regular contractions (>4 per hour)
- Fluid leaking (amniotic fluid)
- Reduced fetal movements
- Severe swelling of face/hands
Australian notes
- Knowing the signs of preterm labour is important. If you experience regular contractions or fluid leaking before 37 weeks, go directly to your hospital or call 000.
- RANZCOG provides a helpful guide on preterm labour signs at ranzcog.edu.au.