Gestational Diabetes

Gestational diabetes is one of the most common health issues that can occur during pregnancy. It happens when the mother is diagnosed with diabetes for the first time partway through the pregnancy. The key to minimizing the effects of gestational diabetes is diagnosing it early through the use of an oral glucose tolerance test. If gestational diabetes is not diagnosed correctly, it can lead to conditions such as macrosomia in the baby (abnormally large fetal size), which puts the baby at risk for complications like neonatal hypoglycemia (low glucose levels) or trauma during delivery. It can also lead to other serious issues such as jaundice, premature birth, birth asphyxia, and reduced uteroplacental perfusion , which harms the child by reducing oxygen flow to the brain.

Gestational Diabetes

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What causes gestational diabetes? 

During pregnancy, the body produces a larger amount of certain hormones that help maintain a healthy pregnancy and provide nutrients to the baby. This increase in hormones can interfere with insulin, a substance which takes glucose (sugar) out of the bloodstream and uses it for energy. This causes higher blood sugar levels, which is normal in pregnancy, as this extra glucose is needed to support the baby. However, when the amount of insulin produced is less than the amount needed to handle blood sugar levels and the amount of glucose in the bloodstream is very high (also known as hyperglycemia), gestational diabetes can occur (1).

Risk factors 

Risk for gestational diabetes may increase if the patient has any of the following conditions (1):

  • A previous diagnosis of gestational diabetes or prediabetes, poor impaired glucose tolerance, or impaired fasting glycemia
  • A family history of type 2 diabetes
  • Advanced maternal age (over 35)
  • Previously birthed a baby that weighed more than 9 pounds
  • High blood pressure and preeclampsia
  • Too much amniotic fluid (polyhydramnios)
  • Significant weight gain before or during the first 18-24 weeks of pregnancy
  • Medical conditions associated with risk for diabetes, such as polycystic ovary syndrome (PCOS)

Signs and symptoms

Generally, it usually does not manifest in any obvious symptoms. However, signs and symptoms for gestational diabetes may include blurred vision, fatigue, frequent infections, increased urination and thirst, and nausea (9). Gestational diabetes can only be diagnosed through routine prenatal testing and screening.


The American Congress of Obstetrics and Gynecologists (ACOG) recommends that all pregnant patients receive an oral glucose tolerance test between the 24th and 28th week of pregnancy to screen for gestational diabetes. People who have risk factors for it may have this test earlier in the pregnancy, typically around the 18th week of pregnancy (1). Starting at 32 weeks of gestation, the mother should have prenatal testing done at least every two weeks, including NSTs, BPPs, ultrasounds and Doppler flow studies. Additionally, ACOG states that women who develop pregnancy-related diabetes should be re-tested 6 to 12 weeks after delivering their babies (1). 

Usually, to test for gestational diabetes, the patient will drink a syrupy solution, and their blood will be tested to check glucose level an hour later. A follow-up test is then given, whereby the patient fasts overnight and then has their blood sugar tested the next morning. After the test, they will drink a solution that has an even higher level of glucose than the syrupy solution given during the initial test. The patient’s blood glucose level will then be checked every hour for a period of three hours. If at least two of the blood glucose readings are higher than normal, the patient will be diagnosed with gestational diabetes (1).

Treatment and management

With gestational diabetes, frequent check-ups by the physician are essential, especially during the last three months of pregnancy, and especially if the patient has factors that make them high-risk. The physician will carefully monitor the patient’s blood glucose levels.

Once a patient is diagnosed with gestational diabetes, the physician will have her monitor her diabetes by testing her glucose level at home. The most common way is to draw a drop of blood from a finger and putting it on a device that will give a glucose reading. The goals of treatment are to keep blood glucose levels within normal limits during the pregnancy and to make sure the growing baby is healthy.

The medical team will also perform other prenatal tests to monitor the baby’s health. These include fetal monitoring (NST),  to check the oxygenation and health of the baby, and ultrasound studies which are essential to watch for abnormal fetal growth associated with gestational diabetes, estimate fetal weight and assess amniotic fluid levels.  

 A biophysical profile (BPP), which uses a scoring system that allows the physician to evaluate the baby’s heartbeat, movements, breathing, and overall muscle tone, and determine whether the baby is surrounded by a normal amount of amniotic fluid. The baby’s scores on heartbeat, breathing, and movement help the physician determine if the baby is getting enough oxygen and is neurologically intact.  Doppler flow studies are also performed to test blood flow to the baby. 

In addition to close monitoring, it is recommended that mothers with gestational diabetes be treated with dietary counseling, oral hypoglycemic medications, or insulin (5).

Gestational diabetes and birth injury

Currently, the American College of Obstetricians and Gynecologists (ACOG) and the American Diabetes Association recommend screening all pregnant women for gestational diabetes. . 

Due to the multiple, serious complications that can arise from untreated gestational diabetes (and even, in some cases, with treatment), rigorous testing and monitoring is important. According to a 2008 study that spanned multiple countries, the Hyperglycemia and Adverse Pregnancy Outcome (HAPO) trial, even subtle defects in maternal glucose metabolism during pregnancy led to health problems for mother and baby (2). 

High-risk pregnancy

Gestational diabetes places mothers in the high-risk pregnancy category, as it poses an increased risk for complications during pregnancy, labor, and delivery. With proper monitoring and care, however, many of the risks associated with gestational diabetes can be mitigated, resulting in a healthy baby.

Mothers who have a high-risk pregnancy are referred to maternal-fetal specialists and require more frequent prenatal testing. In addition, these mothers are often advised to have a scheduled, early delivery in order to minimize the risks associated with their specific high-risk conditions.

Premature birth

In many cases, it is safest for babies of mothers with gestational diabetes to be delivered in a scheduled delivery prior to 40 weeks (3). If a mother’s diabetes is poorly controlled, delivery is recommended as early as week 36 (4). Although premature birth does have associated risks, in the case of diabetes, the benefits of early delivery outweigh the risks, especially with proper postnatal care. 


The high blood sugar levels with gestational diabetes are often passed on to the baby through the placenta (5). This large amount of energy is put towards growth and can result in a baby being too large (macrosomic), which increases the baby’s risk of a traumatic birth, like getting stuck or injured in the birth canal. Babies with macrosomia are most safely delivered via C-section. If macrosomia goes undetected or cesarean section is not performed, this may result in a prolonged or arrested labor, in traumatic injury to the baby or HIE. (6).

Neonatal hypoglycemia

Once babies are born, they begin to produce their own glucose and energy stores. While in utero, babies produce larger quantities of insulin to process the existing larger supply of blood sugar from the placenta.  

When babies from a gestational diabetes pregnancy are born, the amount of insulin they produce does not drop as quickly as their glucose supply does, since they are used to a larger supply of glucose in utero (7). If they don’t take in enough energy as newborns, their blood sugars drop dangerously low. This is extremely problematic because blood sugar is the sole energy source for the brain. If low blood sugar (hypoglycemia) continues, brain cells begin to die, which can cause seizures and permanent brain damage. Generally, after birth, it’s very important to monitor the baby’s blood sugar – especially if their mother had diabetes – in order to prevent it from dipping too low (7).

Hypoxic-ischemic encephalopathy 

Hypoxic-ischemic encephalopathy (HIE) is a brain injury caused by a lack of blood and oxygen flow to the brain. This can happen due to complications associated with diabetes, such as prolonged labor or traumatic delivery due to macrosomia or placental insufficiency (1, 3, 7). Medical practitioners are trained to monitor and recognize the specific events and conditions that could potentially cause injury – and should be trained to avoid injury and provide care that is up to the ‘standard of care.’ If they do not provide proper care, the baby may suffer HIE, which can result in cerebral palsy.

Neonatal seizures

Neonatal seizures are one sign that a baby has neurological abnormalities. Seizures are abnormal electrical discharges in the brain and are very common in the presence of hypoxic-ischemic encephalopathy (HIE), as well as in neonatal hypoglycemia. Neonatal hypoglycemia can damage brain cells, which in turn can cause seizures. It is very important that medical professionals bring seizures under control because continuing seizures can make underlying brain damage worse.

Neonatal jaundice

Mothers with gestational diabetes can sometimes have poor placental perfusion or placental insufficiency, which affects the flow of blood to the baby through the umbilical cord. This can cause the baby to be deprived of oxygen in the uterus (chronic intrauterine hypoxia). These conditions can cause the baby to produce too many red blood cells (7). Babies’ livers break down these red blood cells, releasing a substance called bilirubin into the blood. When too much bilirubin is released (hyperbilirubinemia), the baby’s skin and eyes can turn yellowish. This condition is called jaundice.

Jaundice is a sign that should be reported to a medical professional for immediate treatment. In some babies, jaundice goes away on its own, but in other cases, babies may need some help. When babies need help eliminating bilirubin, they are put under blue phototherapy lights. If jaundice isn’t treated properly, bilirubin can continue to accumulate to toxic levels and cross the blood-brain barrier. If bilirubin reaches the brain, it causes a form of brain damage called kernicterus – a condition which is always avoidable (8).

Inducing Labor

It is common practice to induce labor prior to 40 weeks for women with gestational diabetes as a strategy to reduce complications, especially those related to macrosomia. Labor induction is often planned at 38 ½ to 39 weeks’ gestation and can occur when the baby’s lungs are mature, antepartum tests are normal, diabetes is under control, and the mother doesn’t have vascular disease (1).

ACOG recommends consideration of C-section delivery in diabetic women when estimated fetal weight exceeds 4500 grams. Some researchers recommend considering C-section delivery when the estimated weight is between 4000 and 4500 grams, after evaluating obstetrical history and clinical measurements of the pelvis. Physicians should be alerted to the possibility of cephalopelvic disproportion if dilation or descent stops during labor, and the baby’s estimated weight exceeds 4000 grams. These researchers also suggest consideration of C-section delivery in diabetic women who demonstrate significant protracted labor and failure of descent (1).

Physicians have to consider a number of factors when caring for a woman with gestational diabetes and her baby. Due to the variety and complexity of these issues, it is essential that medical professionals monitor and treat the mother and baby very closely throughout the pregnancy, labor, and delivery.

Legal help 

All pregnant women must be screened for gestational diabetes. It is critical for a pregnant woman’s doctor to accurately read the results of gestational diabetes tests in order to prescribe the correct treatment plan, and plan for a safe labor and delivery to avoid complications and injury to the baby.

If your child was diagnosed with a birth injury, and you suspect it’s from mismanaged gestational diabetes, our  experienced birth injury lawyers at ABC Law Centers can help. Our firm has focused exclusively on birth injury for 25 years, and has handled cases for clients who had mismanaged gestational diabetes. To begin your free case review, you may contact us in any of the following ways below. Not only is the initial consultation free, but you will pay no fees unless we win your case.

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  1. Gestational diabetes mellitus: Screening, diagnosis, and prevention
  2. Hyperglycemia and adverse pregnancy outcomes 
  3. Gestational diabetes mellitus: Obstetric issues and management
  4. Timing of Delivery in Gestational Diabetes Mellitus: Need for Person-Centered, Shared Decision-Making
  5. Gestational diabetes mellitus: Glycemic control and maternal prognosis
  6. Large for gestational age newborn
  7. Infants of women with diabetes
  8. Unconjugated hyperbilirubinemia in term and late preterm infants: Management
  9. Pregnancy Complications: Gestational Diabetes