Meconium Aspiration During Labor & Birth: What You Need to Know

We’ve all heard a story about women being rushed to the O.R. after meconium was found in their amniotic fluid. But was it necessary? Is there anything else you can do to prevent meconium aspiration?

Fetal distress is not the only reason for meconium-stained amniotic fluid. Just like other labor interventions, intervening because of meconium should be based on your specific pregnancy symptoms with a holistic approach to care and not a one-size-fits-all plan.

Meconium-Stained Amniotic Fluid: When Should You Worry?

If your water breaks and you think it may have meconium in it, contact your birth professional immediately. Meconium in the water on its own doesn’t mean baby is in trouble, but it is something your care provider wants to know about right away as it could lead to seizures, cerebral palsy or a rare but serious complication called meconium aspiration syndrome (MAS) for the baby.

Your baby’s age plays a part in whether you should be more concerned. For a baby at 37 weeks, meconium may indicate something more serious, while for a 42-week baby, it is likely denotes a mature digestive tract.

If the amniotic water is brown or golden and well diluted (thin), it suggests that the meconium passed a while ago. This is possible if the baby had a stressful event days or weeks before labor occurred, passed meconium, and now the issue has resolved, according to midwife Maura Winkler. If the amniotic fluid looks greenish and is thicker, then the meconium passed recently. This could be a sign that baby is currently in distress. Again, tell your practitioner right away but try not to worry.

A better marker for to judge for distress is the infant’s heart rate, since some babies who are in distress do not have meconium staining. Your midwife or doctor can assess this, which is why it’s important to contact them immediately if there is the presence of meconium. Essentially, the combination of  meconium-stained fluid and a baby showing signs of distress is reason to worry. In that case, your practitioner will know the best steps to take when overseeing your labor.

How to Tell If There Is Meconium in Your Amniotic Fluid

If your water breaks and it looks murky and green or brown-colored, then it likely has been polluted with meconium. Some amniotic sacs, however, don’t burst until well into labor or rarely even after birth (called en caul). If your water doesn’t break early in labor, that’s OK, it will usually break on its own as labor progresses.

Meconium passage in utero is common. About 15% of babies will pass meconium while in utero. For babies who are post-term, or at 42 weeks gestation, the incidence of meconium present reaches 30%. Of these babies, only 1% to 5% will experience any signs of meconium aspiration syndrome. That means 95% of the babies who aspirate meconium clear their lungs on their own. Meconium in the water is something to be aware of and tell your practitioner about immediately — but not something to stress over before looking at other factors.

What Causes a Baby to Poop In Utero?

Experts don’t know for certain what causes a baby to expel meconium, but they do have some theories as to some potential causes:

Theory #1: The Baby’s Digestive Tract Is Matured

Believe it or not, this is the most common reason for meconium in the fluid. Once the digestive tract is mature, a baby will release its first bowel movement. The reason later term babies are more likely to release meconium in utero is because they are more likely to have matured digestive tracts and an increase of motilin, a hormone responsible for maturation of the intestinal tract and bowel movements. (Older babies are more likely to aspirate meconium because there is a higher ratio of meconium in water.)

Theory #2: Fetal Distress

Toward the end of a pregnancy, especially in post-term pregnancies, the placenta can lose some of its ability to deliver enough oxygenated blood to the fetus. That can cause fetal stress and cause the baby to expel and aspirate meconium in the womb.

Meconium in the water could be a sign of fetal distress, but it’s not an absolute indicator of it. A baby can be in distress and not produce meconium. If your practitioner is concerned about distress, he or she will likely be looking for other markers, too, such as fetal heart rate (the best indicator of fetal distress).

Theory #3: Cord or Head Compression During Labor

Cord or head compression during labor can cause a vagally mediated gastrointestinal peristalsis response, which causes a baby to empty their bowels in utero. This doesn’t necessarily mean that the baby is in distress but will and should be monitored by your health care practitioner.

What Is Meconium Aspiration?

Meconium in the water doesn’t necessarily mean anything serious. But if the baby “breathes in” meconium from the amniotic fluid (called meconium aspiration), it could cause respiratory distress. This happens in only 1% to 4% of live births. Of that, 95% of babies will clear their lungs on their own and won’t need any assistance in breathing.

Meconium Aspiration Syndrome is when the baby inhales the meconium into its lungs. It can make it difficult for the baby to breathe by irritating the airways, affecting the way the lungs expand, or partially or completely blocking the baby’s airways, essentially reducing the amount of oxygen the baby receives.

Meconium aspiration can occur either in the womb or at birth when baby takes his first breaths. The reflex to start breathing doesn’t start working until immediately after birth, so even if meconium is passed early, it isn’t likely that the baby will breathe it in. The exception is that fetal distress may cause gasping in babies earlier than normal, which can lead to meconium aspiration if meconium is present (i.e., if you see it in the amniotic fluid when your water breaks).

What Causes Meconium Aspiration Syndrome?

It was once thought that meconium in the water directly caused meconium aspiration syndrome, or MAS, but evidence is not so sure anymore. It’s now thought that the primary cause of MAS is hypoxia or anoxia, and meconium in the lungs compounds the issues.

Hypoxia is when the baby does not get enough oxygen in utero, and anoxia is when baby gets no oxygen (due to cord compression, distress, etc.) and begins to gulp for air too soon. It’s the gulping for air before birth that can cause MAS to occur. When baby and mom are doing well, there is less risk of gulping for air, thus less risk of meconium aspiration.

Symptoms of Meconium Aspiration

It’s impossible to tell before delivery whether or not the baby has breathed in meconium-stained fluid. After birth, you may notice:

  • Blue- or green-tinged skin
  • Difficulty breathing, including noisy breathing, grunting, or rapid breathing
  • No breathing or crying
  • Limpness and lack of movement
  • Abnormal fetal monitor results

Your midwife or doctor will know these signs of respiratory distress and act immediately.

How to Avoid Hypoxia and Meconium Aspiration

The less stress mom feels, the less stress baby feels. Reducing mom’s stress is a good place to start. Taking a bath once a week, journaling, prayer, yoga, meditation, and pregnancy affirmations are all great ways to lessen stress and have a happy pregnancy.

As far as labor goes, as long as mom and baby are doing fine, mom should be allowed to labor at home as long as she desires (or have a home birth if she has planned one). Choosing a birth place you are comfortable in, choosing attendants and guests with discernment, and being prepared with pain management techniques are excellent ways to keep mom — and subsequently baby — comfortable, relaxed, and ready for the birth.

Mom should be allowed to labor how and where she feels most comfortable. Mom knows best what positions, sounds, and movements are going to give baby the easiest passage out. Even if you don’t think you know now what you’ll want during labor, once the time comes, your birthing mama instinct will kick in, and then it’s on you to really tune in and listen to that intuition. Forcing mom to lay on her back if it’s uncomfortable to her can cause more stress for mom — and baby.

Other things you and your birth team should know to avoid hypoxia, which could cause your baby aspirating meconium are:

  • Remembering that meconium on its own is not necessarily concerning. Stay relaxed during labor.
  • Avoiding interventions that could increase fetal distress, such as artificially rupturing membranes, the administering of pitocin, and directed pushing
  • Having a vaginal birth, which can help clear baby’s airway the lungs compress as they go through the birth canal. Let baby descend naturally, and push as your body tells you to.
  • Leaving the cord intact after birth until it stops pulsating to allow baby an easier transition to breathing.

Your midwife or doctor will also keep tabs on baby’s heart rate to be sure he is doing well. Remember that heart rate is a better indicator of whether baby is distressed.

Should I Consider Labor Induction?

There is a greater chance of meconium aspiration after 40 weeks gestation because babies between 40 and 42 weeks are much more likely to have a mature digestive tract and begin passing meconium. Fear of MAS is not a good reason to induce labor. Generally, a low-risk pregnancy can go to 42 weeks gestation (or later) safely. Your practitioner will closely monitor your baby as you get closer to 42 weeks to be sure everything is A-OK.

If you need to consider inducing, start with natural methods to induce labor like nipple stimulation and drinking a small amount of castor oil. Some people have expressed concern that if mama drinks castor oil, it can cause baby to have his first bowel movement. The study supporting this doesn’t factor in the likelihood of post-date women trying castor oil, or the likelihood of post-date babies passing meconium in utero. Discuss your options with your health care professional to see if they recommend induction in your situation. Also check your bishop score to help you decide if induction is right for you.

Treatment for Meconium Aspiration

In some cases, intervention may not be necessary, but it is important to have a birth team on standby in case of crisis (midwives are trained for this). If the baby is born with a strong and steady heartbeat, is active and breathing clearly, then no treatment is needed. If, however, breathing is labored or the heart rate is low, then intervention is necessary.

To treat meconium aspiration syndrome, the priority is to make sure that baby is getting enough oxygen. If the baby is not breathing well, it will be given an oxygen mask and suction. Other interventions the baby may receive are:

  • Placement in intensive care
  • Antibiotics to treat an infection (preventative antibiotics are not shown to reduce incidence of MAS)
  • An oxygen tube to keep blood oxygen levels normal
  • A warming machine (or skin to skin contact to keep baby warm)
  • Airway suctioning (The National Institute of Health recommends suctioning after delivery.)
  • Using a surfactant replacement for better oxygenaton
  • Inhaled or systemic steroids like budesonide to improve oxygenation
  • A ventilator (this is usually only used in serious cases)
  • Nitric oxide treatment (an inhaled gas that helps maintain blood flow and oxygen in the lungs)
  • Extracorporeal membrane oxygenation (a type of heart/lung bypass only used in very severe cases)

It’s important after meconium aspiration to closely monitor the baby for signs of complications. The condition usually clears up in 2 to 4 days, but severe cases requiring ventilation could mean long-lasting respiratory damage. In very severe and rare cases, it can cause seizure disorders, poor brain development or even death.

What Meconium Staining Means for Baby and Your Labor

If you have meconium-stained amniotic fluid, you may begin to worry about what this means for the rest of your labor, especially if you were planning a birth center birth or home birth. First of all, don’t panic. Call your health care provider to discuss the best options for you based on all of your labor symptoms.

If you are using a midwife, some midwives are required to recommend transferring to the hospital when meconium is present. Others will allow labor to continue at home or at a birth center as long as baby and mom are doing well. If your midwife suspects fetal distress, she will recommend transferring to the hospital. If you do need to transfer to the hospital, you may still be able to have a low-intervention birth, so don’t stress!

It’s important to have a health care provider whom you trust and who has your best interests in mind. Each scenario is different and must be looked at holistically. A baby born at 37 weeks with thick, fresh meconium in the water is much more concerning than a baby born at 42 weeks with well-diluted, old meconium in the water.

Final Word on Preventing Meconium Issues

Keep in mind that meconium staining may be caused by stress to the baby, so take time throughout your pregnancy for relaxing self-care. This can reduce stress for you and baby. Preparing mentally and physically for childbirth is a great way to have confidence in your own body and prevent fear in labor. Make sure you have a flexible birth plan and a birth team you trust.

How about you?

Did you have meconium in your amniotic fluid when your water broke? Were there any complications? Were you planning a home birth or birth center birth but transferred to a hospital when you spotted meconium? We’d love to hear your stories in the comments section below.

 

About the Author

Genevieve Howland is a childbirth educator and breastfeeding advocate. She is the bestselling author of The Mama Natural Week-by-Week Guide to Pregnancy and Childbirth and creator of the Mama Natural Birth Course. A mother of three, graduate of the University of Colorado, and YouTuber with over 75,000,000 views, she helps mothers and moms-to-be lead healthier and more natural lives.

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