Fetal Macrosomia

Nationwide Cerebral Palsy Resource Network

Macrosomia means “of large body.” The term is used to describe a newborn who is overly large. Sometimes, the greater the size and weight of the child, the more likely it is that complications will occur.

When a child is larger than average, it could cause a vaginal delivery to be extremely difficult. It puts a baby at risk for birth injuries and other medical problems. If medical personnel failed to reasonably anticipate fetal macrosomia or provide treatment during delivery, please call (800)462-5772 for free to find out how Stern Law, PLLC can help.

What are the causes and risk factors associated with macrosomia?

In the United States, approximately 10 percent of all births involved a child diagnosed with macrosomia. There are a number of reasons why children develop macrosomia. The most common and influential factor associated with cases of macrosomia are abnormally high maternal sugar levels from gestational diabetes or diabetes mellitus. Additional cases and risk factors include:

  • Delayed birth;
  • Maternal impaired glucose tolerance;
  • Overdue pregnancy;
  • Being of Hispanic descent;
  • Having a male child;
  • Excessive maternal weight gain;
  • Genetics;
  • Having delivered previous children diagnosed with macrosomia;
  • Maternal obesity;
  • A mother and/or father of a larger size;
  • Genetics;
  • Advanced maternal age.

If you have any of the risk factors associated with fetal macrosomia, it is important to speak with your doctor during prenatal visits. It is also advised that you ask your doctor as many questions as possible, such as:

  • What is the underlying cause of fetal macrosomia;
  • What kinds of treatment options exist to prevent your child’s out-of-control growth;
  • How will fetal macrosomia affect a pregnancy;
  • When macrosomia is suspected, what are the labor and delivery options;
  • Is a cesarean section (c-section) the best option;
  • What tests, if any, are required to confirm macrosomia;
  • Does a baby need special care after birth;
  • Has the physician successfully delivered a child with macrosomia;
  • Should you consult with a physician with specific knowledge of macrosomia.

What are the complications of delivering a child with macrosomia?

Fetal macrosomia can cause significant complications for a mother and her child, both during labor and after delivery. The scope of complications for a mother includes the following:

  • Labor problems – Macrosomia may cause your child to become lodged in the birth canal, potentially requiring the use of forceps and other invasive devices and methods to free the child. This can lead to injuries to the birth canal such as lacerations, vaginal and perineal tearing, excessive bleeding during delivery and a fractured tailbone;
  • Uterine rupture – If you had a Cesarean section in a previous pregnancy or major uterine surgery, macrosomia increases the risk of uterine rupture. Uterine rupture is a rare yet serious complication in which the uterus tears along the scar line of a previous c-section or uterine surgery. Oftentimes, an emergency c-section is necessary to prevent life threatening complications associated with uterine ruptures;
  • Bleeding after delivery – Macrosomia increases the risk that your uterine muscles will not properly contract after giving birth, referred to as uterine atony (a condition that involves the loss of tone in the uterine musculature). This can cause excessive bleeding post-delivery.

Complications a child might experience include:

  • Birth injuries – A child who is macrosomic may experience shoulder dystocia during delivery, referring to a situation where his or her shoulder becomes stuck behind a mother’s pubic bone and cannot pass through the birth canal. Children who are overly large as a result of shoulder dystocia can also sustain several different types of head, shoulder, neck, spinal cord and nerve injuries as well as fetal distress caused by hypoxia should delivery be delayed;
  • High blood sugar levels – A child diagnosed with macrosomia is more likely to be born with impaired glucose tolerance, or higher than average blood sugar levels, which present risks to the newborn requiring treatment to avoid brain injuries;
  • Obesity – Research studies suggest that babies who are born with macrosomia have a higher likelihood of being obese as a child and later in life;
  • Metabolic syndrome – This refers to a series of medical conditions that occur simultaneously, such as hypertension, high blood sugar levels, excess body fat and abnormally high cholesterol levels. Should a child be diagnosed with macrosomia, he or she is at a greater risk of developing metabolic syndrome in the future.

What are the symptoms of macrosomia?

The most common symptoms of macrosomia are excessive fetal growth during pregnancy and delivering a child weighing in excess of eight pounds, 13 ounces. Additional signs and symptoms of macrosomia are:

  • Large fundal height – Fundal height is a measurement of the distance between the pubic bone and the top of the woman’s uterus;
  • A higher than average volume of amniotic fluid – Medically referred to as polyhydramnios, this condition is marked by too much amniotic fluid. The amount of fluid that surrounds and protects your baby while in utero may indicate that your baby is overly large. The amount of amniotic fluid reflects your unborn child’s urine output – the larger the child, the more urine he or she produces.

If you have experienced any of the above signs and symptoms of macrosomia, it is important for your doctor to assess the extent of your child’s condition, determine a potential underlying cause, and discuss with you the safest labor and delivery options safely accounting for fetal macrosomia.

If you or your child sustained injuries because a doctor didn't take your baby's size into account, please call Stern Law, PLLC at (800)462-5772 for a free consultation to discuss your legal options.