All You Should Know About Meconium

Babies pass their first bowel movement known as ‘meconium’ a few days after birth. Meconium is basically a sticky, tar-like substance that has a green-black appearance and is just the waste that was produced in your baby’s intestine during pregnancy. At times babies pass meconium before or during labor. In case meconium is noticed once the mother’s water break, it can lead health care providers to become seriously concerned about the wellbeing of her baby. 

Also, your baby may even pass meconium shortly after birth, even if he is yet to feed. But for a majority of babies, it will pass after they start breastfeeding as the nutrient-dense colostrum will have a laxative effect, thereby helping your baby pass his first few sticky bowel movements.

To be honest, all babies have meconium and will pass it through their bowel movements at some point – hopefully after they are born though. For the record, meconium is known to contain cells, amniotic fluid, mucus, bile and lanugo that is stored in the intestines while in utero. Now, there are a few things that you should know about meconium, a few of which are:

7 What Exactly is Meconium?

Babies are known to swallow amniotic fluid on a regular basis from around 14 weeks of pregnancy. Believe it or not, the amniotic fluid plays a vital role in fetal development and is known to contain things like lanugo, mucus, intestinal cells, water and bile. The amniotic fluid then passes through to the developing baby’s small intestine, which then removes and absorbs the water. If there is any debris left behind, it gets passed on to the large intestine. 

When this debris starts building up, it begins to form a sludgy tar-like substance known as meconium. As your baby reaches full-term, the meconium that has long been building in his large intestine tends to fill up most of the space within that intestine. As time goes by, your breasts start producing colostrum in the first few days after birth. Amongst the many benefits that this substance has to offer, one that stands out is that of its laxative effect. 

Because of this, it assists in moving the meconium from your baby’s bowel. This typically happens within the first 12 hours after the birth of a full-term baby. For the record, caregivers may suspect intestinal obstruction in case your baby does not pass meconium within 48 hours of birth.

Green tinted amniotic fluid

At times babies pass their first meconium while still in the womb, well before their mother-to-be’s water breaks. If this happens to you, your amniotic fluid is going to be tinted green. In most cases of hospital birth in which the baby has passed meconium before birth, a special NICU team is going to be called in right after delivery in case the meconium was ingested into the baby’s lungs.

6 What Passing Meconium Before Birth Means

In case a baby passes meconium before birth, the amniotic fluid is going to be stained and will therefore have a greenish appearance. If this happens, the baby is also going to be covered in meconium, particularly if there’s a lot of vernix (waxy coating on the baby’s skin). Most importantly, the baby may even swallow meconium (don’t confuse this with aspiration), but the good news is that this will not be harmful for him.

A major reason why babies pass meconium before birth is that their digestive systems have matured in the womb. What this means is that babies are more than likely to pass meconium before birth the longer they go past their due dates. A sudden and short compression of the head or cord can also make a baby pass meconium. 

In such a case, there is a momentary lack of oxygen, which makes the sphincter muscles relax, thereby making it possible for the meconium to be pushed out. The fact of the matter is that the heads of babies are rather compressed in the final moments of birth, which is why some have a trail of meconium upon birth.

Fetal distress

Although the exact cause of a baby passing meconium cannot be determined, it is also believed to be related to fetal distress in some babies. When the thick meconium gets mixed into the amniotic fluid, it gets swallowed and breathed into the airways of the baby. As the baby takes his first few breaths after delivery, the meconium particles enter the airways and can easily get inhaled deep into the lungs.

5 Information About Meconium Aspiration Syndrome

All through pregnancy, a baby’s lungs get filled with amniotic fluid, and if meconium is present, it can get inhaled into the airways. If a baby is severely distressed during labor and lacks oxygen for a while, there’s a good chance that he will gasp and inhale any meconium that might be present. 

When inhaled, meconium can partially or even completely block the baby’s airways, thereby making it extremely hard for him to breathe and hence reducing the amount of oxygen that he receives. Meconium Aspiration Syndrome or MAS can also trigger a chemical irritation within the airways and eventually make it harder for the baby to breathe. 

Apart from that, inactivation of surfactant by the meconium is also possible together with infection of the lungs. For those who don’t know, surfactant is a substance that assists the lungs in expanding properly. From the 20% of babies born with meconium stained amniotic fluid, nearly 2-5% are expected to develop MAS. The symptoms of MAS include rapid breathing, Cyanosis (blue colored skin), low APGAR scores and over-distended chest.

Diagnosis of meconium aspiration

The key to diagnosis lies in the presence of meconium in the amniotic fluid. The healthcare provider may also perform a chest X-ray to diagnose meconium aspiration. A diagnosis is required because meconium in the lungs can trigger problems with respiration and increase the risk of infection. For 3-5% of these babies it can result in death, but remember there are often other issues occurring along with the MAS such as prematurity.

4 Can Meconium Be Dangerous?

A great deal of concern is typically caused if a woman’s water breaks and is found to be stained with meconium. In case the color of the water is a bit greenish, it means that the meconium has just recently been passed by the baby. However, if it is yellowish or brownish in appearance, it means that the meconium was passed sometime earlier and is fairly old. 

A major reason why this is such a concern is because the baby might end up having meconium on his lungs in such a case, thereby suffering from Meconium Aspiration Syndrome (MAS). The fact of the matter is that meconium can trigger a lot of problems in case it gets inhaled into the lungs. In about 5% of babies that are born in meconium-stained amniotic fluid, the thick, tarry meconium will get inhaled, plug the baby’s small airways and hence lead to respiratory distress. 

In such a case, it’s necessary for the distressed baby to be delivered quickly so that their mouth and nose can be suctioned as soon as they’re delivered, thereby preventing meconium aspiration.

A few more statistics

Nearly 30% of kids who develop meconium aspiration pneumonias have to be put on mechanical ventilators. A few of these have some residual lung problems (wheezing, coughing) even 5 or 10 years later and a small number die from meconium aspiration, which shows just how dangerous it can be.

3 Treatment for Meconium Aspiration

According to the guidelines presented by the American Academy of Pediatrics, babies who inhale meconium should not be suctioned intra-partum or during birth. Back in the days, it was common for such babies to be suctioned as soon as their head was delivered. This is no longer a standard practice.

In cases where a baby that has inhaled meconium appears active and well ,and also has a good heart rate of more than 100 beats per minute, it’s necessary for care providers to monitor the baby for signs of MAS that may appear in the first 24 hours after birth. However, if the baby is not active after inhaling meconium, has a low heart rate of under 100 beats per minute and is limp with poor muscle tone, the care provider is likely to suction the baby immediately. 

With that, the baby’s airways are going to be cleared as much as possible to limit the amount of meconium that has been inhaled. For this purpose, they insert a tube into the baby’s windpipe by means of the nose or mouth. With that, the baby is likely to spend a bit of time in the NICU to be monitored for signs of infection. Such babies may also require blood tests along with oxygen treatment.

What about severe MAS?

Babies that have severe MAS may go on to develop pneumonia. A majority of babies with severe MAS will also experience lung infections and wheezing in the first 12 months of life. However, their condition will improve as their lungs continue to develop new air sacs.

2 Can MAS be Avoided?

MAS can typically be avoided by preventing your baby from getting stressed. For this, it’s highly recommended for pregnant women to have a supportive and calm birth environment. In case the laboring woman is disturbed and overly stressed all through the labor process, it can lead to slow or stalled contractions. In turn, this may trigger a cascade of interventions so as to hurry it along, which is only going to add to the baby’s distress.

There are quite a few interventions that are particularly known to add to a baby’s distress, thereby raising their chances of experiencing fetal distress. Some of these include constant fetal monitoring, artificial rupture of membranes (breaking the waters) and induction or augmentation with artificial oxytocin. In case your water breaks and is found to be meconium stained, then you’re likely to be monitored, which will reduce your ability to move. 

If the meconium is thin and your care provider established that your baby’s heart rate is fine, it’s best for you to deliver your baby in an upright birth position so that the contractions can push fluid from your baby’s lungs and out of the nose and mouth. It’s also best for the cord to be allowed to continue pulsating to provide oxygen to your baby while transitioning to breathing air into the lungs.

Something to remember

You need to bear in mind the fact that meconium staining can also occur even if your baby is not distressed. While you’re at it, it’s not necessary at all for all babies who pass meconium to become stressed. It’s rarely a problem and can easily be avoided by refraining from the utilization of interventions that can add to your baby’s distress.

1 Information About Meconium Peritonitis

This condition basically occurs when the baby’s bowel is ruptured before birth. In this condition, the bowel basically opens and a hole forms in it. With that, the meconium continues to leak out into the space that surrounds the bowel – known as the peritoneum – thereby leading to an inflammation in the lining or the abdomen or peritonitis. Infants that have cystic fibrosis have an increased risk of experiencing meconium peritonitis.

The diagnosis of meconium peritonitis is rather easy. To begin with, it can be diagnosed before birth in case the doctor notices areas of calcium deposits in the peritoneum during an ultrasound scan. However, for a diagnosis to be performed after birth, the baby will probably experience vomiting and have an enlarged abdomen. In such a case, an X-ray needs to be performed to see whether the bowel is enlarged or dilated. 

A baby’s bowel may rupture due to underlying problems including imperforate anus (where the anus is not open), microcolon (an abnormally narrow lower section of bowel) and volvulus or twisting of the bowels etc.

What about treatment?

In a majority of cases, the bowel continues to heal on its own while the baby is still in the womb. However, in other cases, surgery may need to be performed on the baby in order to fix the underlying problem.

A baby who has meconium peritonitis will need to be carefully monitored with regular ultrasounds. Babies who are diagnosed with such a problem before birth are typically delivered at a hospital that has a specialized neonatal intensive care unit.

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