Fetal Macrosomia

Every parent wants the best for their children. This starts from day one. When parents get asked if they’d rather have a boy or girl, most say, “I just want a healthy baby.” Sadly, this isn’t always what parents get. Many babies are injured during birth or shortly thereafter. One example of this that’s worth knowing about is called fetal macrosomia.

What Is Fetal Macrosomia?

At the heart of the problem of fetal macrosomia is that the baby is simply much larger than most at the time of birth. Something this small can be enough to cause big problems later on.

When the weight of an infant is estimated to be above 90% the average weight of babies at the same gestational age, they are considered to be large for that period. The other factor that plays a role in fetal macrosomia is if the pregnancy is already considered risky because the child or mother may be experiencing preexisting medical problems.

Most doctors would say that a baby who is at nine pounds, 15 ounces is at a birth weight in the macrosomia range. Others would start getting concerned at eight pounds, 13 ounces.

For how scary it can be, macrosomia is fairly common. According to the American Academy of Pediatrics (AAP), a little more than 10% of all pregnancies in this country result in macrosomia.

As you can imagine, a baby this big and other potential problems make giving birth quite difficult, even dangerous. That’s why labor is often induced early, or a cesarean section is prescribed.

Symptoms of Fetal Macrosomia

What makes matters even worse is that fetal macrosomia is often very hard to diagnose during pregnancy. However, there are a few tests that can be used to catch potential symptoms early.

One is checking for an excessive amount of abdominal fluid. During a prenatal visit, a doctor can measure how much amniotic fluid is present via ultrasound. Too much of it may indicate that the infant is bigger than expected.

Fundal height is another indicator. Physicians can measure the distance between the pregnant woman’s uterus and pelvic bone. The result is what is called a fundal height measurement and can give the physician a better idea of how large the child has become.

Causes of Fetal Macrosomia

As we are already covered, the cause of fetal macrosomia is that the child is too big at the time of birth. The question is, then, how did the child become so big that it became a problem?

One of the main causes is maternal diabetes. Mothers are obese can put an infant at risk too. In either case, the infant is getting far too many nutrients while in the womb, which allows it to get to such a large size.

Post-term pregnancies can lead to this complication and much for the same reason. Women who have already had large infants should be concerned too. For whatever reason, Hispanic women have a disproportionate chance of having a child with fetal macrosomia. Mothers over the age of 35 are also a higher risk of giving birth to larger babies. Males are more likely to be born largely too.

Medical Malpractice and Fetal Macrosomia

Obviously, fetal macrosomia is caused, mainly, by the mother and decisions they make before giving birth. However, if your child is born with this complication, the surgeon may still be guilty of medical malpractice in the eyes of the law. To put it simply, they have the training to diagnose the problem before it becomes a much bigger one. If it’s determined they failed to do so, you have a strong case.

No matter what, if your child is born with fetal macrosomia, it’s worth speaking to another doctor about possible medical malpractice and talk to an attorney as well.


  1. https://www.birthinjuryguide.org/birth-injury/causes/fetal-macrosomia/
  2. https://www.medmal1.com/article/failure-to-recognize-fetal-macrosomia