Second trimester · 23 weeks pregnant
Week 23: lungs in training
Blood vessels grow in the lungs and hearing is sharp.
The lungs are developing the blood vessels and structures needed to breathe air, although they are far from ready. Your baby hears well now and may jump at a slammed door.
Size and weight
About the size of
a grapefruit
Length
28.9 cm
Weight
500 g
Averages from standard growth charts. Measured crown to rump until week 20 and head to heel afterwards.
How your baby is developing
- Blood vessels form in the lungs in preparation for breathing.
- The skin is still thin, wrinkled and translucent, with visible blood vessels.
- Hearing is acute: the baby startles at loud noises and settles to familiar voices.
- Rapid eye movements begin, a sign of maturing brain activity.
How you may feel
- Swelling in the feet, ankles and fingers
- Braxton Hicks
- Backache
- Bleeding gums
- Tingling or numb fingers (carpal tunnel)
- Food cravings
Carpal tunnel symptoms come from fluid pressing on the nerve in the wrist. A night splint and shaking out your hands help; it usually resolves after birth.
What's next
Tests and appointments
No routine tests this week. Keep taking your vitamins and contact your polyclinic with any concerns.
What to do this week
- Drink plenty of water; dehydration makes swelling and Braxton Hicks worse.
- Keep up your pelvic floor exercises.
- Get your blood pressure checked at every visit and know the signs of preeclampsia.
Call your doctor or maternity hospital if
- Any vaginal bleeding, or fluid leaking from the vagina
- Regular, painful tightenings or period-like cramps
- A severe headache, blurred vision, or sudden swelling of your face and hands
- Severe or persistent abdominal pain, fever, or pain when you pass urine
If something feels wrong, trust yourself and call 103 or your maternity hospital. You will never be wasting anyone's time.
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