Trimester 2
Week 21
Your baby is about the size of a carrot.
Length: 26.7 cm · Weight: 360 g
Common this week: Braxton Hicks contractions, Baby hiccups felt, Hair/nail growth, Heartburn, Leg cramps.
Baby development
- The baby is swallowing amniotic fluid, practising for feeding after birth.
- Rapid eye movement (REM) sleep is occurring — the baby may be dreaming.
- Bone marrow is now producing all blood cells (taking over from the liver).
- The digestive system is practising, producing first meconium (dark sticky stool).
Changes for you
- You may feel rhythmic fluttering movements — this is the baby hiccuping.
- The uterus is about 1 cm above the navel.
- Braxton Hicks contractions (painless, irregular tightenings) may begin.
- Hair and nails often grow faster due to prenatal hormones.
Tips
- Braxton Hicks are normal — if contractions become regular or painful, contact your midwife.
- Start researching baby equipment needs — the layette list can be overwhelming, so start early.
- If you notice shortness of breath, discuss with your provider.
- Iron-deficiency anaemia is common at this stage — your next blood test should check iron levels.
Appointments
- Routine antenatal check — blood pressure, urine, fundal height, baby's heartbeat.
Warning signs
- Regular painful contractions before week 37
- Watery discharge (may be amniotic fluid)
- No fetal movement in 24 hours
Australian notes
- In NSW, if you are planning a public hospital birth, this is a good time to register if not already done.
- Sydney-based families may wish to explore the NSW Midwifery Group Practice (MGP) model for continuity of care.