Fetal macrosomia is a condition that occurs during pregnancy where the baby becomes abnormally large for its gestational stage.
What is the definition of fetal macrosomia?
About 1 out of every 10 pregnancies in the U.S. involves macrosomia. Fetal macrosomia complicates as many as 50 percent of pregnancies in women with gestational diabetes and 40 percent of pregnancies complicated by type 1 and type 2 diabetes, including some women treated with intensive glycemic control. Delivery of an infant weighing greater than 4,500g occurs 10 times more often in women with diabetes as compared with a population of women with normal glucose tolerance. Most medical malpractice cases involving birth injuries and macrosomia involve mother’s
Fetal macrosomia is a condition that automatically makes any pregnancy high risk because it makes normal delivery extremely difficult. Macrosomia is long been linked with numerous perinatal and maternal complications. Diligent monitoring and timely diagnosis of fetal macrosomia are therefore very important. Doctors need to manage this risk to avoid awful consequences.
The most serious complication of fetal macrosomia is shoulder dystocia. When birth weight exceeds 4500 grams, the risk of shoulder dystocia is increased with rates reported from 9.2% to 24% in pregnant women without diabetes and to 19.9% to 50% in pregnancies complicated by diabetes.
How Is Fetal Macrosomia Diagnosed?
Diagnosing fetal macrosomia might seem like a relatively simple thing to do. The doctor just checks the size of the baby before delivery. Unfortunately, it is not quite that simple because there is no easy method for weighing a fetus in the womb. Doctors use a combination of ultrasound imaging, amniotic fluid levels, and fundal height measurements to make a diagnosis of macrosomia.
Ultrasounds and sonograms provide images of the fetus but not accurate weight measurements. Doctors can use an ultrasound in the 3rd trimester to take measurements and use them to estimate fetal weight, but this is notoriously inaccurate. It seems paradoxical but earlier ultrasounds are more significant, particularly when they are part of a continuing pattern.
Measuring amniotic fluid is another method of monitoring fetal weight. An excessive amount of amniotic fluid (combined with other indicators) can be used to diagnose fetal macrosomia. Fundal height is another measurement used to monitor fetal weight. Fundal height is basically the distance between the uterus and the top of the mother’s pelvic bone. A shorter distance between the two is an indicator of large fetal size and weight.
Diagnosis of fetal macrosomia also involves the recognition of various symptoms and risk factors by doctors in earlier stages of pregnancy. Known risk factors for fetal macrosomia include both pre-gestational and gestational diabetes. These conditions increase the risk of fetal macrosomia and shoulder dystocia. The babies of diabetic mothers have a greater shoulder-to-head and chest-to-head disproportion than babies of similar size delivered by non-diabetic mothers. This has real significance When the baby’s weight is greater than 7.7 pounds the risk of shoulder dystocia is two to three times higher in diabetic women than in non-diabetic women.
Other risk factors include a prior history of macrosomia, high glucose, obesity, and diabetic preeclampsia. Recognition and timely diagnosis of fetal macrosomia is critical in preventing delivery complications.
What Can Happen If Fetal Macrosomia is Not Diagnosed?
If timely diagnosed, fetal macrosomia can usually be handled safely by an early C-section delivery. The standard of care required the health care providers to consider the use of a C-section for delivery of the baby and discuss with the mother the option for and against a C-section because of the higher risk of shoulder dystocia and subsequent brachial plexus injury.
If fetal macrosomia is not properly diagnosed, however, it can result in hazardous complications during delivery. If the baby is too big it is much more likely to get stuck in the birth canal. Delivery complications such as shoulder dystocia are far more likely to occur in cases of undiagnosed fetal macrosomia. When these complications arise the doctors in the delivery room must resort to emergency techniques and tools all of which often lead to birth injuries. Damage to the brachial plexus can result in total or partial paralysis of the baby’s upper extremity (Erb’s Palsy). If there is oxygen deprivation, cerebral palsy is also a grave risk.
But it is just not the misdiagnosis of macrosomia that leads to birth injuries and medical malpractice lawsuits. Our lawyers also see cases where the doctors knew full well the risk of macrosomia and proceed without considering how delivery options change with suspected macrosomia. One common mistake, and you will see this in the settlements and verdicts below, is using a vacuum to deliver a child that is thought to be over 4,500g. The medical literature is clear that a vacuum is counterindicated for these babies. Too many obstetricians either do not know this or choose to proceed anyway.
Why Is Macrosomia the Biggest Risk Factor for Shoulder Dystocia?
Macrosomia the biggest risk factor for shoulder dystocia because it is difficult to remove a larger baby during delivery. The bigger the baby, the greater the likelihood that when the baby’s head comes out, the shoulders, torso, or abdomen will get stuck in the pelvis. The gravest risk is the shoulders behind the pubic bone.
Why Is a Mom with Gestational Diabetes at Greater Risk for Shoulder Dystocia?
Babies whose mothers have gestational
diabetes often produce larger babies with more fat. So when diabetes is not properly controlled, the fetus is at significant risk for macrosomia simply because the fetus is exposed to high glucose levels that it converts to fat. That fat is often in the shoulder, torso, and abdomen, the same places that are sometimes hard to clear the material public bone during delivery.
Why Is Failure to Perform a C-Section a Common Thread in Many Microsomia-Related Birth Injury Lawsuits?
If an ultrasound or other testing methods reveal a baby that may be too large to deliver safety, an elective Cesarean can greatly reduce the possibility of shoulder dystocia or nerve damage. So, as you will see in the sample macrosomia-related settlements below, birth injury lawsuits often allege that a reasonable doctor would have recommended, or at least offer, the mother a choice of a C-section when faced with the risks of delivering an excessively large baby. In some cases, it may be a breach of the standard of care not to strongly recommend a C-section rather a trial of labor.
Settlements & Verdicts for Failure to Diagnose Fetal Macrosomia
Below is a summary of jury verdicts and settlements in malpractice cases where injuries resulted from a failure to diagnose fetal macrosomia.
- G.L. v. United States (South Carolina 2022) $1,000,000: Baby suffered birth-related nerve avulsion and/or rupture of the brachial plexus of his right shoulder, leading to permanent limited motion of his right arm during difficult vaginal delivery. The lawsuit accused the defendants of failing to consider risk factors indicating the fetus was possibly macrosomic and at risk for shoulder dystocia; failing to appropriately manage labor to avoid shoulder dystocia.
- Cudney v. United States (Utah 2020) $956,504: Shoulder dystocia was encountered during vaginal delivery and baby suffered severe brachial plexus damage resulting in Erb’s palsy. The lawsuit alleged that the doctors were negligent in failing to to diagnose fetal macrosomia in ultrasound 2 weeks before delivery, which should have led them to opt for a C-section delivery.
- D.S. v. Udeh (California 2019) $975,000: A macrosomic baby boy suffered meconium aspiration, hypoxia, and micro bleeding. He developed cerebral palsy, ADHD, and cognitive and developmental delays. His mother claimed the obstetrician failed to recognize macrosomia and negligently delayed a C-section. The parties agreed to a $975,000 settlement.
- M.W. v. Bloch (New York 2019) $926,358: A macrosomic baby girl sustained a brachial plexus injury and neuropathy. Her mother claimed the certified nurse-midwife failed to order appropriate physical exams and failed to properly deliver a macrosomic baby. This case settled for $926,358.
- NA v Erhart (New York 2019) $850,000: Defendants OB/GYN and hospital were allegedly negligent in failing to diagnose fetal macrosomia despite the presence of risk factors (including gestational diabetes). Had macrosomia been timely diagnosed baby could have been delivered via scheduled C-section. Instead, the baby became stuck during vaginal delivery and excessive force was used during vacuum extraction efforts. As a result baby’s brachial plexus nerves were damaged causing Erb’s palsy with partial paralysis of the right arm. The jury awarded $850,000.
- Manning v Pecos Valley (New Mexico 2018) $73,030,000: Mother with history of diabetes was admitted for labor and delivery. Fundal height measurements indicated baby was macrosomic but no diagnosis of fetal macrosomia was made and doctors went ahead vaginal delivery instead of preemptive C-section. Baby became stuck in birth canal and suffered prolonged oxygen deprivation causing hypoxic-ischemic brain injury. Excessive force during vacuum extraction also damaged baby’s brachial plexus nerves. Baby was born with severe brain damage with cognitive impairment and partial arm paralysis. Defendants were allegedly negligent in failing to recognize and formerly diagnose macrosomia. Jury awarded huge verdict of $73 million.
- A.G. v. Hamilton Hosp. (Pennsylvania 2017) $250,000: plaintiff alleged malpractice based on doctor’s failure to diagnose fetal macrosomia which resulted in delivery complications including shoulder and head dystocia. Baby suffered nerve injuries causing Erb’s Palsy. Damages of $250,000 were awarded.
- P.B. v. Rush Copley Med. Center. (Illinois 2013) $1,500,000: This case involved the negligent failure to diagnose fetal macrosomia leading to shoulder dystocia and significant permanent injuries to baby. Plaintiff alleged that the injuries could have been avoided if macrosomia was properly diagnosed and a pre-emptive c-section delivery was done instead. This birth injury lawsuit ultimately settled for $1.5 million.
- Bergman v. Kelsey (Illinois 2006) $1,700,000: The doctors and hospital in this case were sued for negligently failing to test for and diagnose fetal macrosomia. Plaintiffs alleged that had they diagnosed fetal macrosomia, they would have known that a vaginal delivery was unsafe. Complications arose during delivery and the baby died before an emergency C-section could be performed. The hospital settled separately for $250,000. The claims against the doctors went to trial and the jury awarded $1.7 million.
- Doe v. Roe (California 2006) $700,000: Permanent paralysis of the left arm of baby occurred when responding to should dystocia. Plaintiff claimed injuries could have been avoided had doctor properly diagnosed fetal macrosomia. Doctor disputed whether macrosomia was the actual cause of the shoulder dystocia. Jury awarded $700,000.
Contact Miller & Zois About Failure to Diagnose Fetal Macrosomia
The attorneys at Miller & Zois handle birth injury cases in Maryland. We are very familiar with malpractice claims related to failure to diagnose fetal macrosomia. If you delivered a baby with birth injuries resulting from the doctor’s failure to diagnose fetal macrosomia you may be entitled to compensation, call us at 1.800.553.8082 or submit a request for a free consultation.
- Committee on Practice Bulletins—Obstetrics. Macrosomia: ACOG Practice Bulletin, Number 216. Obstet Gynecol 2020; 135:e18.
- Beta, J, “Maternal and neonatal complications of fetal macrosomia: systematic review and meta-analysis”. Ultrasound in Obstetrics & Gynecology. 54 (3): 308–318. doi:10.1002 (September 2019). Author talks about clear statistical evidence of the risks of macrosomia yet there is still little guidance given to OBs on how to manage these risks. Doctors and nurses in labor and delivery have to at least understand the scope of these risks to provide the best possible care to minimize the risk of adverse outcomes.
- Cohen B, Sonographic Prediction of Shoulder Dystocia in Infants of diabetic mothers. Obstet Gynecol 1996; 88:10-13 (infants of diabetic mothers 10 times as likely to weigh more than 10 pounds).
- Acker DB, Risk Factors for Shoulder Dystocia, Obstet gynecol 66;762,1985 (C-section is suggested for diabetic moms if the estimated fetal weight is over 8.8 pounds).
- Gonen R, Is Macrosomia Predictable, and Are Shoulder Dystocia and Birth Trauma Preventable? Obstet Gynecol 1996;88:526-9(same as Acker, C-section if over 4000 grams for diabetic women. Gonen’s work has long been cited by defense lawyers for the proposition that C-sections do not significantly decrease the incidence shoulder dsytocia. ACOG and some of the authors of related studies are not subtle about injecting language designed to protect obstetricians from birth injury lawsuits).
- ACOG Practice Patterns Number 7, October 1997. Shoulder Dystocia (macrosomia and maternal diabetes are the two risk factors most strongly associated with shoulder dystocia… a planned cesarean delivery may be reasonable… ultrasonography could correctly identify macrosomia 60% of the time and 88% in one study.)
- Leikin EL, Abnormal glucose screening tests in pregnancy: a risk factor for fetal macrosomia, Obstet Gynecol 1987; 69:570-573 (women with abnormal glucose test had higher incidence macrosomia which suggests patients with minor abnormalities of carbohydrate metabolism during pregnancy are at risk for delivering a macrosomic infant).
- Elliott, JP, Ultrasonic prediction of fetal macrosomia in diabetic patients. Obstet Gynecol. 1982; 60: 159-162 (strongly recommends a C-section for any baby over 4,250 grams with diabetic mother).