Trimester 3
Week 29
Your baby is about the size of a sweet potato.
Length: 38.6 cm · Weight: 1150 g
Common this week: Nocturia, Pelvic pain, Heartburn, Back pain, Braxton Hicks, Fatigue.
Baby development
- The baby's muscles and lungs continue to mature rapidly.
- The head is growing to accommodate the rapidly developing brain.
- White fat deposits are forming under the skin, giving a rounder appearance.
- The baby may have developed a preference for a particular position.
Changes for you
- You may feel more uncomfortable lying on your back — always sleep on your side.
- Pelvic girdle pain may be more pronounced.
- Frequent urination at night (nocturia) is very common.
- Your belly may feel very tight and uncomfortable at times.
Tips
- Sleep on your left side — this is particularly important in the third trimester for optimum blood flow.
- Prepare your hospital bag — ideally ready by week 36, but many pack earlier.
- Do daily pelvic floor exercises.
- Consider a birth preferences document (often called a birth plan) — keep it flexible.
Appointments
- Routine antenatal check.
Warning signs
- Severe back pain that is new and constant
- Watery or bloody discharge
- Contractions before 37 weeks (preterm labour)
- Reduced fetal movement
Australian notes
- The Safer Baby Bundle is an Australian initiative recommending women sleep on their side in the third trimester. Research shows this can reduce the risk of stillbirth.
- Information on stillbirth prevention: stillbirthfoundation.org.au or call SANDS (miscarriage, stillbirth & newborn death support): 1300 072 637.