Your Baby at 23 Weeks

A Closer Look at Week 23

At 23 weeks, your baby's lungs are practising for the most important transition they will ever make: the moment they take their first breath of air. Although the lungs are not yet mature enough to function independently, your baby is performing rhythmic breathing-like movements, inhaling and exhaling amniotic fluid. These practice movements strengthen the muscles of the diaphragm and chest wall and help stimulate lung maturation.

Your baby's skin is still translucent and reddish at this stage, because subcutaneous fat has not yet accumulated in significant quantities. Blood vessels, bones, and organs are visible through the thin skin. Over the coming weeks, layers of fat will be deposited beneath the skin, smoothing out wrinkles, adding padding for temperature regulation, and giving your baby the plump, rounded appearance that characterises newborns.

Braxton Hicks contractions may begin to appear around this time. These are your uterus's 'practice contractions' — brief, irregular tightenings that are not painful (though they can be uncomfortable) and do not indicate labour. They are thought to help tone the uterine muscles in preparation for delivery. Braxton Hicks are often triggered by dehydration, a full bladder, or physical activity, and they typically stop when you rest and drink water.

If you experience contractions that are regular, increasing in frequency, or accompanied by pain, back ache, or pressure, contact your healthcare provider to rule out preterm labour. At 23 weeks, every day the baby remains in the womb is beneficial for lung and brain development, so any signs of preterm activity should be assessed promptly.