When a baby weighs much more than average, both the mother and the baby may face certain risks. This complication is known as fetal macrosomia. Technically, it applies to any baby who weighs more than eight pounds, 13 ounces. A higher risk of complications applies to a baby with a birth weight greater than nine pounds, 15 ounces.
The causes of fetal macrosomia are not always easily identified, but often obesity, diabetes, or significant weight gain during pregnancy is linked to this complication. Fetal macrosomia becomes more likely with each successive pregnancy, and it is more likely to occur in male infants. A history of giving birth to a very large infant also increases the risk of this event happening again. Other risk factors include age (over 35) and a pregnancy that extends past the due date by more than two weeks. In unusual cases, fetal macrosomia may indicate a medical condition involving the growth of the fetus. This may cause a doctor to advise diagnostic testing.
Symptoms and Diagnosis of Fetal Macrosomia
A doctor may suspect fetal macrosomia if the distance from the top of the uterus to the pubic bone of the mother is greater than normal. This is known as fundal height. In addition, a condition known as polyhydramnios may indicate fetal macrosomia. Polyhydramnios involves excessive amniotic fluid around the baby in the womb.
Amniotic Fluid and Fetal Size
Amniotic fluid correlates to urine output, which in turn may correlate to fetal size and certain medical conditions that might spur fetal growth.
In some cases, a doctor might identify fetal macrosomia after conducting an ultrasound near the end of a pregnancy. The ultrasound measures certain body parts of the baby, and a doctor can convert those measurements into a formula that predicts their overall weight. Ultrasounds do not always identify fetal macrosomia, though. A doctor also might conduct a non-stress test if they are concerned about the baby. A non-stress test checks the heart rate of the baby in response to their movements. Sometimes a doctor might conduct both an ultrasound and a non-stress test to form a fetal biophysical profile. This can reveal the presence of polyhydramnios, as well as any movement or breathing issues.
Complications of Fetal Macrosomia
One of the most serious complications of fetal macrosomia is shoulder dystocia, which occurs when the shoulder of a baby is trapped behind the pubic bone of the mother. Shoulder dystocia can lead to brain damage and other permanent or even life-threatening conditions. A mother also may suffer from heavy bleeding after childbirth or from uterine rupture, which usually involves tears in the uterus near the scar lines from previous surgeries. This is an emergency that requires an immediate C-section to save the baby. Less grave complications include tears in the vaginal tissues and perineal muscles.
Meanwhile, a baby who suffers from fetal macrosomia may face a greater risk of childhood obesity. They also may develop problems involving their blood pressure, blood sugar, cholesterol, and body fat around the waist, which may lead to heart disease, stroke, or diabetes. These conditions are known collectively as metabolic syndrome.
Treatment for Fetal Macrosomia
Doctors usually do not induce labor in response to fetal macrosomia, since this does not tend to resolve the complications associated with it. Sometimes a mother can proceed with a vaginal birth, but often a doctor will recommend a C-section if certain risk factors are present. Alternatively, they might monitor the mother for complications during labor and prepare for the possibility of a C-section if vaginal birth proves too risky. If a mother proceeds with a vaginal birth, fetal macrosomia may require a doctor to use forceps or other devices to assist with delivery.
Factors Supporting a C-Section
The mother of a child weighing nine pounds, 15 ounces or more suffers from diabetes
The child weighs 11 pounds or more
The mother previously had a child who suffered from shoulder dystocia
Babies with fetal macrosomia may be placed in a neonatal intensive care unit (NICU) for further treatment and monitoring. They may suffer from hypoglycemia, which is a low level of blood sugar that can affect the brain. Excessive production of red blood cells, known as polycythemia, may cause slower blood flow and clots in a baby with fetal macrosomia.
Compensation for Errors Involving Fetal Macrosomia
If a doctor does not properly address fetal macrosomia, the mother and the baby may suffer devastating injuries. For example, a failure to recommend a C-section when it would have been appropriate can lead to shoulder dystocia or uterine rupture during a vaginal birth. In other cases, errors using forceps or vacuum extractors during the birth of a large child can cause brachial plexus injuries and other types of nerve damage. When this happens, a family can sue a medical provider for compensation.
Damages in birth injury lawsuits may cover the costs of medical treatment and the pain and suffering endured by the mother and the child. To get compensation, a family usually would need to prove through expert testimony that a doctor failed to meet the professional standard of care. This means that they did not do what a competent doctor in their specialty would have done when treating complications of fetal macrosomia. Retaining persuasive experts and battling defense attorneys can be challenging without the assistance of an experienced attorney. Parents who suspect medical malpractice should consult birth injury lawyers in their area to find out whether they have a viable claim.