A weekly breakdown from 21 to 24 weeks
Your baby’s arms and legs have grown and are now more in proportion with the body. The eye lids which have previously been closed and sealed are now beginning to separate. The pancreas is starting to make enzymes to breakdown food for digestion. A growth spurt is likely at this point as your baby’s stomach is now equipped to absorb energy boosting nutrients from the amniotic fluid that is swallowed. However, most of your baby’s nourishment is still coming directly from the placenta. Your baby is the size of a carrot and hair follicles are pigmenting to determine hair colour.
The nervous system is highly functioning and the nerve cells between the brain and spinal cord are making connections. Your baby can recognise warmth, light, sound and pain. Currently the size of a papaya, your baby is most likely lying in the transverse position across the tummy. Movements are becoming more distinct as the muscles mature. The developing grasp reflex is encouraging baby to grab its ears, nose and umbilical cord. The placenta is processing one litre of blood per hour and this increases to twelve litres of blood per hour by forty weeks gestation.
Your baby is practicing breathing inside the womb but still receiving all oxygen requirements from the placenta. The lungs have started to produce surfactant, a substance that helps the lungs stay inflated when breathing air after birth. Your baby is the size of a grapefruit and the pancreas is producing insulin. A fine layer of fat is forming between the muscle tissues and skin, covering the blood vessels making baby’s complexion less translucent. Your baby may experience hiccups caused by the sudden and irregular contraction of the immature diaphragm.
Your baby is the size of a corn cob. The inner ear is forming which controls balance and hearing. Your baby can recognise and respond to sounds including your voice. The startle reflex has developed so you may observe your baby jumping at the sound of loud noises. Movements can often be felt from the outside now and you are able to share this exciting experience with family members. Your baby is gaining weight rapidly to assist in retaining body heat and regulating temperature.
Written by PBC Expo Midwife Hayley Hall
Midwife, Birth Educator and Mum of 4
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