• The baby is overdue; the baby’s gestational age is more than 40 weeks (postmaturity).
• “Aging” of the placenta if the pregnancy goes far past the due date (placental insufficiency).
• Decreased oxygen (fetal hypoxia) to the baby while in the uterus.
• Diabetes in the pregnant mother (gestational diabetes).
• Difficult delivery or prolonged labor.
• The pregnant mother develops high blood pressure and protein in her urine after the 20th week of pregnancy (preeclampsia).
• Drug abuse by the pregnant mother (tobacco or cocaine use).

• Fast heart rate on the electronic fetal monitor.
• Slow heart rate on the electronic fetal monitor that occurs at or after the peak of a uterine contraction (late decelerations / non-reassuring heart tracings).
• Greenish or yellowish appearance of the amniotic fluid.
• The baby’s skin, umbilical cord, and / or nailbeds are stained green.
• The baby is not breathing, or has fast or labored breathing after birth.
• Bluish skin color (cyanosis).
• Slow heartbeat (bradycardia).
• A  larger than normal chest and rib cage (barrel chest).
• Low Apgar score. (An Apgar score is an assessment of the newborn the first few minutes of life that considers factors such as the baby’s skin color / complexion, pulse rate, reflexes, muscle tone and breathing.)
• The baby’s blood at the moment of birth, umbilical cord blood, is acidic (has a low pH).
• Meconium in the baby’s trachea.
• At birth, the baby appears weak, with a loss of muscle and body mass (hypotonia).
• The baby is limp at birth.

Inhalation of meconium can be confirmed by one or more of the following tests:

• The health care team listen’s to the baby’s chest with a stethoscope and hears abnormal breath sounds, especially coarse, crackly sounds.
• An analysis of the baby’s blood shows acidic blood (low pH), decreased oxygen, and increased carbon dioxide.
• A chest x-ray shows patchy or streaky areas in the baby’s lungs.  The lungs appear overinflated, and the x-ray shows collapse of multiple small areas of the lung.  In addition, the heart appears larger than normal.

If a baby is at risk for MAS, foetal monitoring should be done in order to prevent dangerous complications.  If the baby is not receiving enough blood or oxygen, or if the baby’s heart rate is slow, doctors must act quickly to restore blood flow and oxygen supply.  If oxygen and blood supply cannot be restored, an emergency delivery, usually a C-section, should be performed.  It is essential that a team skilled at reviving newborn babies be present at the delivery if meconium staining is found in the amniotic fluid.  A failure to adequately monitor the baby, or a delay in emergency delivery can cause significant brain damage, injury, or even death of the baby.

Treatment of MAS includes the following:

• Airway clearance: Deep airway clearing, called suctioning, is recommended only for non-vigorous / depressed babies who have a risk for MAS.  A depressed baby has absent or slow breathing (apnea or bradypnea), a slow heart rate (bradycardia), and low muscle tone (hypotonia).  Initial suctioning should not exceed five seconds. If no meconium is retrieved, repetitive suctioning is not required. However if meconium is retrieved and no bradycardia is present, it is recommended that the baby be suctioned again, with oxygen being given right before and after suctioning.
• Neonatal Intensive Care Unit: A baby at risk for MAS who shows signs of respiratory distress should be admitted to the neonatal intensive care unit (NICU).  Close monitoring of the baby is essential since he or she can deteriorate very quickly.  Once the baby develops MAS, maintenance of good oxygenation, ventilation and blood pressure, and correction of acidic blood, low blood sugar and other metabolic disorders is the main focus of treatment.
• Breathing machine (ventilator): About 30% – 50% of babies with MAS require a machine, called a ventilator, to help them breathe.  One reason for this is because their lungs have areas of collapsed lung tissue, as well as airflow obstruction and inflammation throughout.  The ventilator controls the oxygen and carbon dioxide levels within the baby’s blood, and makes it easier and safer to suction meconium, mucus and other secretions that are common in babies with MAS.
• Supplemental oxygen: Some babies with MAS do not need a machine to help them breathe, they just need a little extra oxygen.  The oxygen can be delivered through an oxygen hood, nasal cannula or face mask.
• Surfactant therapy: Surfactant is a substance that occurs naturally in the lungs.  Surfactant decreases the tension in the lungs and helps make the lungs compliant (easy to expand).  When babies have meconium in their lungs, the meconium interferes with the the function of the surfactant, which can make it very difficult for the baby to breathe and  for the baby’s lungs to function properly.  Surfactant in drug form often is given to babies with MAS to help improve their lung function, reduce the severity of respiratory distress and decrease the likelihood of respiratory failure.
• Steroid therapy: Meconium in the lungs causes an inflammatory response in the airways.  Providing steroid treatment for babies with MAS may help reduce the inflammation and inflammation side-effects of meconium, thereby improving the baby’s lung function.
• Nitric oxide: A condition called persistent pulmonary hypertension (PPHN) often accompanies MAS.  PPHN occurs when the newborn baby’s circulation does not adapt to breathing outside the womb.  PPHN causes the blood pressure in the arteries of the lungs to be very high, and a large portion of the baby’s blood bypasses the lungs and this blood, therefore does not receive oxygen.  This can be life-threatening.  Inhalation of nitric oxide causes the dilation (relaxation) of the vessels in the lungs and improves oxygenation of the baby.
• Extracorporeal membrane oxygenation (ECMO): In extracorporeal membrane oxygenation (ECMO), a machine that takes blood from the body, oxygenates it using an artificial lung, and pumps it back into the body using an artificial heart, is used. ECMO is similar to a heart/lung bypass machine used in open heart surgery, but can be used for a longer period of time.  ECMO is used for babies whose low oxygen levels (hypoxia) cannot be corrected with other treatments, such as by putting them on a ventilator and giving them extra oxygen to breathe.
• Radiant warmer to maintain body temperature