Meconium aspiration syndrome (MAS)

Meconium is the medical name for a newborn baby’s first faeces (poo). Meconium is dark green, thick and sticky and contains the material that the unborn baby ingested in their mother’s womb. Once the baby starts feeding on colostrum and milk, their faeces become more yellow.

It is normal for a baby to pass dark green, sticky meconium in the hours immediately after birth. It is also common for the amniotic fluid, which drains from the mother in labour after her waters break, to be discoloured or ‘stained’ with meconium.

During labour and delivery, if the amniotic fluid contains significant  meconium this can also indicate ‘fetal distress’. This is because when a fetus (unborn baby) is not getting enough oxygen their intestinal activity increases. This relaxes the anal sphincter allowing meconium to pass into the amniotic fluid that surrounds the baby.

If the baby inhales or ‘aspirates’ meconium into their lungs, such as by gasping for oxygen, their airway can become blocked by sticky or lumpy meconium

Meconium aspiration syndrome (MAS) occurs when a baby inhales (or aspirates) meconium which has been passed into the amniotic fluid which surrounds them during labour and birth. The sticky or lumpy meconium can block the newborn baby’s airway, making it difficult for them to breathe oxygen.

If the meconium is not cleared quickly from the baby’s trachea (windpipe) and lungs, it can result in respiratory distress, causing (or increasing an existing episode of) oxygen deprivation, leading to HIE brain injury or the baby’s death.

A baby who is suffering from respiratory distress as a result of meconium aspiration may show the following signs:

• breathing rapidly;
• grunting;
• retraction (pulling in) or distention (pushing out) of their chest;
• cyanosis (blue skin colour from reduced oxygen saturation).

Meconium can be a sign of fetal distress. If dark green or black, thick or lumpy meconium drains from the mother after her waters are broken in labour this should warn the midwives that the unborn baby might be suffering from distress.

When there are signs of fetal distress, such as meconium, the labour and delivery must be monitored and managed carefully to avoid injury to the baby.

In these circumstances, correct care should usually include:

• continuous electronic monitoring of the fetal heart rate and maternal contractions by cardiotocograph (CTG);
• review by an obstetrician (doctor) if meconium and other abnormalities mandate urgent delivery of the baby;
• expedited delivery by forceps, Ventouse (kiwi) or caesarean section.

Preparations should also be made for the birth of a baby who might have aspirated meconium, to avoid delay in restoring the baby’s oxygen supply. This includes warning the neonatal unit paediatricians that a baby with possible meconium aspiration is about to be born. The paediatricians should attend the delivery, fully equipped and ready if needed to clear the baby’s airway and lungs and provide resuscitation or ventilation. 

Meconium can cause hypoxic brain injury (HIE) by blocking the newborn baby’s airway and making it difficult for them to breathe in oxygen at birth.

Meconium is also one of many warning signs during labour and delivery which should alert midwives to the possibility that lack of oxygen is causing fetal distress.

Acute hypoxia, a short but profound period of oxygen starvation during labour and birth, can permanently damage a baby’s brain in a matter of minutes. Any delays in delivery of a baby who is suffering from lack of oxygen (hypoxia) can result in permanent injury to their brain.

Delayed action to clear meconium from the baby’s airway (to allow them to breathe) or to provide resuscitation immediately after birth can extend the length of time that the baby is without oxygen. In some cases, this additional delay in restoring the baby’s oxygen supply after birth can turn a reversible episode of hypoxia into irreversible brain injury and permanent disability, or death.

Severe meconium aspiration after delays in delivering the baby, clearing the airway and resuscitating the newborn baby at birth, can lead to permanent disability from:

• hypoxic brain injury or HIE;
• cerebral palsy;
• developmental disability;
• motor (muscle movement) or physical disability;
• learning disability.

The amount of compensation that can be claimed after meconium aspiration causes HIE birth injury depends on the child’s disability, its impact on their life and the cost of meeting the additional needs, losses and expenses that are caused by their disability.  

Claims arising from meconium aspiration and HIE brain injury or cerebral palsy, may include compensation for:

• pain, suffering and disability;
• costs or care and case management;
• therapies (physiotherapy, occupational therapy (OT), speech and language therapy;
• increased costs of suitable accommodation or home adaptations;
• specialist equipment, vehicles and assistive technology (IT);
• costs of surgery or medical treatment;
• loss of earnings and pension;
• support with special educational needs (SEN);
• Court of Protection deputyship.