Cerebral palsy caused by meconium aspiration

What is meconium?

Meconium is the medical term for the thick, tar-like, sticky, dark green, first faeces of a newborn baby, which contains the material ingested by the fetus (unborn baby) in the womb. The baby’s faeces become more of a yellow colour once the baby starts feeding on colostrum and milk. 

What does it mean when meconium is present during labour and delivery?

It is completely normal for a baby to pass meconium (dark green, sticky faeces) in the hours immediately after birth. During labour, after the pregnant mother’s waters break, it is also common for the amniotic fluid which drains vaginally to be discoloured or stained with meconium. 

If meconium is present in the mother’s amniotic fluid during labour and delivery, it might indicate that the fetus is suffering from distress. When a fetus experiences hypoxia (lack of oxygen) its intestinal activity increases, relaxing its anal sphincter (which controls the release of faeces) and passing meconium into the surrounding amniotic fluid. If the meconium is then inhaled into the baby’s lungs, e.g. if the baby gasps because it lacks oxygen, the baby’s airways can be blocked by the sticky or lumpy meconium.

Is meconium a sign or a cause of brain injury?

It is both. It is normal for a fetus or a newborn baby to pass meconium, but it is also one of the signs of fetal distress in labour. If meconium is ‘aspirated’ (inhaled) but is not cleared out of baby’s airway and lungs immediately after birth when the baby needs to breathe in air, the meconium can block the baby’s airway, preventing it from breathing, leading to oxygen deprivation, brain damage and death.

How should the presence of meconium in labour affect the mother’s maternity care?

Significant (dark green or black, lumpy or thick) meconium drainage after rupture of the mother’s membranes should alert the midwives who are caring for the mother in labour to the potential for fetal distress and the need for very careful management of the labour and delivery.

If meconium is present, the fetal heart-rate and maternal contractions should be monitored continuously by CTG (cardiotocograph). If, in addition to meconium, there are any other abnormalities, the midwives should call an obstetrician to review the labour and decide whether delivery should take place urgently by instrumental (forceps or Ventouse) delivery or by caesarean section. 

The neonatal unit paediatricians should be warned that the birth of a baby with potential meconium aspiration is about to take place and they should attend the delivery, fully equipped and ready, if necessary, to act quickly to clear the baby’s airways and lungs, resuscitate or ventilate the baby if needed.

Any delay in delivering a baby who is suffering from distress, or in clearing their airway and resuscitating them immediately after birth, can increase the duration of the baby’s oxygen deprivation and lead to severe brain damage, permanent disability or death. Where the baby suffers acute hypoxia (a short, profound period of oxygen deprivation) it takes just minutes for the baby’s brain to be damaged. Delays in clearing the baby’s lungs and airway or in providing resuscitation after birth can turn a reversible episode of hypoxia into an irreversible brain injury with lifelong, severe disability.

What are the signs of a baby with severe respiratory distress from meconium aspiration?

Short term signs of respiratory distress caused by meconium aspiration may include:

• Rapid breathing.
• Grunting
• Retraction (pulling in) or distention (pushing out) of the chest
• Cyanosis (blue skin colour from lack of oxygen saturation)

Severe meconium aspiration can lead to permanent disability, such as:

• Cerebral palsy
• Developmental disability
• Physical disability
• Learning difficulties