Fetal Macrosomia: How Doctors Deliver Large Babies

Fetal Macrosomia: How Doctors Deliver Large Babies

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Canadian parents have filed a new medical malpractice lawsuit, accusing their doctors and hospital of failing to order a cesarean section in the birth of an oversized baby, the National Post reports.

Quebec Lawsuit: Doctors Failed To Perform C-Section

The child, born seven years ago, weighed 13 pounds at the time of his delivery. The average baby, on the other hand, weighs between 5.5 and 8.8 pounds, according to the US National Library of Medicine. The Canadian mother’s child was, to speak frankly, extremely large. Yet, as the boy’s parents claim in their new birth injury lawsuit, doctors at a Quebec hospital failed even to evaluate the child’s size prior to delivery, let alone recommend the c-section plaintiffs believe was necessary.

Now residents of Quebec, the family is seeking $1.4 million in damages. Court documents reviewed by reporters claim the couple’s child was born with permanent paralysis in one of his arms. The mother, the lawsuit continues, endured extensive vaginal tearing.

In their lawsuit, the parents point to several risk factors that an independent expert testimony should have served as clear warning signs to the Canadian birth team. Among these risks? The mother had previously experienced a “difficult pregnancy.” The true question at the core of this case, however, will be whether or not cesarean section would have been the accepted standard of care in delivering an extremely-large child.

Macrosomia: Is Cesarean Section The Answer?

Watchful Waiting GraphicWhile cesarean section presents its own battery of risks, most obstetricians consider the procedure a life-saving intervention for some women and infants. But fetal macrosomia, diagnosed in infants with a birth weight over 8 pounds 13 ounces (8.8 pounds), is not necessarily among them.

The majority of medical experts believe that, instead of electing to go forward with a c-section immediately, doctors and patients are better-served by “watchful waiting” (at least when fetal macrosomia is suspected).

There is one general exception to this guideline. For babies with a birth weight over 11 pounds, prophylactic cesarean delivery is a well-supported intervention. In managing the deliveries of these very large babies, the American Congress of Obstetricians and Gynecologists (ACOG) says, cesarean section should be strongly considered.

Risk Factors & Complications

In a 2000 clinical guideline, ACOG outlined the primary risk factors for fetal macrosomia:

  • history of fetal macrosomia
  • maternal pre-pregnancy weight
  • weight gain during pregnancy
  • multiparity (twin, triplet or higher multiple birth)
  • male fetus (male babies, on average, are larger than female babies)
  • gestational age more than 40 weeks
  • ethnicity (Latina women have a higher rate of fetal macrosomia than others)
  • maternal birth weight (mother’s weight at time of delivery)
  • maternal height
  • maternal age younger than 17 years
  • results of a blood glucose test

Many women who vaginally deliver macrosomic infants experience severe birth trauma. Fetal macrosomia can also pose severe consequences for children. Larger babies are far more likely to experience shoulder dystocia, a labor complication that can lead to oxygen deprivation, brain damage and nerve injuries.

Cesarean section can reduce these risks significantly, but it’s not the first-line approach recommended by most obstetricians. To understand why, we’ll have to look a little deeper into the condition of fetal macrosomia.

Managing Fetal Macrosomia: A Difficult Proposition

The problem in managing fetal macrosomia is two-fold.

On the one hand, the condition is difficult to diagnose before a child is delivered. Traditional diagnostic techniques, maternal risk factors, clinical examination (palpation) and ultrasound, are imprecise, ACOG wrote in 2017. Birth weight  can only be known after delivery; before that, doctors only suspect that a child may be too large for a safe vaginal delivery. This consideration would seem to militate against the hasty order of a cesarean section. There is always a chance that the doctor has over-estimated the child’s birth weight. If that’s true, vaginal delivery may be the safer choice.

The second problem, however, proposes a strong argument in favor of induced labor or c-section. Infants grow continuously inside the womb. A large child will only get larger. Thus, in cases of fetal macrosomia, the risks posed by the condition continue to grow the longer doctors wait. That’s why ACOG considers “gestational age more than 40 weeks” to be a significant risk factor for fetal macrosomia; fetuses older than 40 weeks are almost necessarily larger than younger fetuses.

Imperfect Options & Difficult Decisions

Faced by a suspected diagnosis of fetal macrosomia, doctors find themselves in a bind. One option is to wait, in hopes that the child is smaller than expected and can be delivered vaginally. The other option is to deliver the child immediately.

Neither choice is perfect. Waiting, as we’ve seen, leads to larger babies, making already-dangerous vaginal deliveries even more dangerous. The benefit of patience, however, is that one could avoid entirely the risks and complications associated with c-section and / or induced labor. Choosing to intervene immediately, on the other hand, runs straight toward those potential risks.

Experts Discourage Induction Of Labor

Labor induction, according to the American Family Physician, is almost never the appropriate choice.

Labor induction often fails, at which point many obstetricians choose to perform a c-section. In many cases, therefore, an attempt to induce labor will revert to cesarean section, the invasive procedure doctors were trying to avoid in the first place.

Syringe GraphicIn fact, a meta-analysis that gathered the results of multiple studies in 2000 found that labor induction did not improve birth outcomes for children with high birth weights. Women for whom induction was attempted underwent c-sections and instrument-assisted deliveries at the same rates as women in whom induction was never tried.

ACOG supports this conclusion, writing that “suspected fetal macrosomia is not an indication for induction of labor because induction does not improve maternal or fetal outcomes.”

Current Clinical Guidelines

The upshot? Current medical standards suggest that, for all but the largest macrosomic babies, obstetricians should allow vaginal delivery to begin naturally, but watch closely for signs of a problem.

Cesarian Section GraphicOnly in emergency circumstances should a cesarean section be the first-line choice, specifically in cases of midpelvic delivery – when a child fails to move forward after reaching the middle of their mother’s pelvis. In the past, doctors chose to manage a midpelvic delivery through the use of birth-assistive devices, like forceps or vacuum extractors, but recent research shows that instrumental delivery poses far higher risks than c-section. Some studies on fetal macrosomia also suggest that cesarean section should be indicated to end prolonged second stages of labor, but this conclusion is still disputed.

As we mentioned above, there’s only one exception to these general guidelines – along with the widespread hesitancy to endorse c-section for larger babies. Cesarean section is indicated in the delivery of children suspected to be 5,000 grams (11 pounds) or more. In women who have been diagnosed with pregestational or gestational diabetes, c-section becomes indicated when the fetal weight is estimated to be 4,500 g (9.9 pounds) or more.

By | 2017-12-08T08:48:00-05:00 August 17th, 2017|Birth Injuries|Comments Off on Fetal Macrosomia: How Doctors Deliver Large Babies

About the Author:

Michael Monheit, Esq. is an experienced medical malpractice and mass torts lawyer. Michael is the parent of a child with developmental delay and special needs. He also sits on the board for The Cleft Lip And Palate Foundation of Smiles. Michael has been appointed as lead plaintiffs' counsel, litigation group chair, and/or plaintiffs steering committee member in several mass tort lawsuits. He has been in practice since 1989.