Fetal macrosomia is a condition that occurs during pregnancy where the baby becomes abnormally large for its gestational stage. There is no universal definition. But macrosomia is generally acknowledged when the baby is over 9 lbs. at birth. It is often also defined as a disproportion between the size of the head and the shoulders and the abdomen.
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 4,500 g occurs 10 times more often in women with diabetes as compared with a population of women with normal glucose tolerance.
Fetal macrosomia is a condition that automatically makes any pregnancy high risk because it makes normal delivery extremely difficult. Diligent monitoring and timely diagnosis of fetal macrosomia are therefore very important. Doctors need to manage this risk to avoid awful consequences.
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 macromsomia.
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 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 nondiabetic 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 nondiabetic women.
Other risk factor 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.
If timely diagnosed, fetal macrosomia can usually be handled safety 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 leads to birth injuries such as Erb's Palsy and Cerebral Palsy.
Below is a summary of jury verdicts and settlements in malpractice cases where injuries resulted from a failure to diagnose fetal macrosomia.
- 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 vaccum 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 Coopley Med. Center. (Illinois 2013) $1,500,000: In this case 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 an pre-emptive c-section delivery was done instead. Claims were settled for $1.5 million.
- Bergman v. Kelsey (Illinois 2006) $1,700,000: Doctors and hospital in this case were accused of negligently failing to test for and diagnose fetal macrosomia. Plaintiff 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 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.
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.References
- Committee on Practice Bulletins—Obstetrics. Macrosomia: ACOG Practice Bulletin, Number 216. Obstet Gynecol 2020; 135:e18.
- 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).
- 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).