Gestational Diabetes is a type of diabetes in which women have glucose intolerance, during pregnancy.
What are the other Names for this Condition? (Also known as/Synonyms)
- Diabetes of Pregnancy
- Gestational Diabetes Mellitus (GDM)
- Glucose Intolerance during Pregnancy
What is Gestational Diabetes? (Definition/Background Information)
- Gestational Diabetes is a type of diabetes in which women have glucose intolerance, during pregnancy. It is characterized by a high blood sugar, first diagnosed during pregnancy
- In other words, Gestational Diabetes is classically defined as having any degree of glucose intolerance, with onset or first recognition, during pregnancy
- Hormonal changes during pregnancy blocks insulin from performing its normal functions, thereby increasing blood glucose levels in pregnant women
- A diagnosis is made through testing blood glucose levels and glucose tolerance test, and the condition is usually treated using a combination of diet modification and medication
- The prognosis of Gestational Diabetes is good with close monitoring of the condition and appropriate treatment
Two subtypes of Gestational Diabetes exist and these include:
- Type A1 Gestational Diabetes
- Type A2 Gestational Diabetes
Who gets Gestational Diabetes? (Age and Sex Distribution)
- Gestational Diabetes occurs in approximately 4% of all pregnancies
- Pregnant women, typically over the age of 25 years, are prone to this condition
- Women, who are African American, Afro-Caribbean, native American, Hispanic, Pacific Islander or Asian, are more likely to have Gestational Diabetes
What are the Risk Factors for Gestational Diabetes? (Predisposing Factors)
Women are at a greater risk for developing Gestational Diabetes, if they:
- Are older than 35 years of age, when pregnant
- Have a family history of the condition
- Have given birth to a baby weighing over 9 pounds (about 4 Kg), or to a baby with birth defects (in a previous pregnancy)
- Have had Gestational Diabetes in a previous pregnancy
- Have high blood pressure (pre-eclampsia or eclampsia of pregnancy)
- Have an excess of amniotic fluid (polyhydramnios)
- Have polycystic ovary syndrome (PCOS), one of the most common female endocrine disorders
- Have been previously diagnosed with impaired glucose tolerance
- Have sugar in the urine (glucosuria)
- Have had an unexplained miscarriage or stillbirth
- Were overweight before pregnancy, with a body mass index (BMI) of 30, or even higher
It is important to note that having a risk factor does not mean that one will get the condition. A risk factor increases one's chances of getting a condition compared to an individual without the risk factors. Some risk factors are more important than others.
Also, not having a risk factor does not mean that an individual will not get the condition. It is always important to discuss the effect of risk factors with your healthcare provider.
What are the Causes of Gestational Diabetes? (Etiology)
The cause of Gestational Diabetes is as follows:
- Food taken into the body is broken down to produce glucose, which then enters the bloodstream. The pancreas produces the hormone, insulin, which facilitates the movement of glucose, from the bloodstream to the cells
- During pregnancy, a woman’s placenta, connecting the baby to her blood supply, produces high levels of pregnancy-related hormones. Most of these pregnancy-related hormones impair the action of insulin in cells, raising blood sugar levels. However, a modest elevation in blood glucose levels, following a meal is normal during pregnancy
- As the baby develops, the placenta produces more pregnancy-related insulin-blocking hormones. In Gestational Diabetes, the placental hormones cause a rise in blood glucose to a level, which can affect the development of the baby
What are the Signs and Symptoms of Gestational Diabetes?
In most cases, there are no symptoms for Gestational Diabetes, or the symptoms are rather mild and not life-threatening. Blood sugar levels are usually restored after delivery.
In others, the signs and symptoms of Gestational Diabetes may be significant and may include:
- Blurred vision
- Frequent infections, such as those of the bladder, vagina, and skin
- Increased thirst (polydipsia), frequent urination
- Nausea and vomiting (polyuria)
- Increased appetite
- Weight loss
How is Gestational Diabetes Diagnosed?
In a majority of women, the onset of Gestational Diabetes usually occurs, halfway through pregnancy. A few diagnostic tools to help diagnose Gestational Diabetes include:
- All pregnant women should have an oral glucose tolerance test done, between the 24th and 28th week of pregnancy, in order to test for the condition
- A blood sugar level above 140 mg/dL is recognized as abnormal
- Testing for HbA1c levels in blood
- Once diagnosed, the women can test their glucose levels at home. The most common testing method is by pricking the finger and using a drop of blood; which when placed in a machine (glucometer), giving a glucose reading. A record of the glucometer readings should be kept as a log, for your healthcare provider
Many clinical conditions may have similar signs and symptoms. Your healthcare provider may perform additional tests to rule out other clinical conditions to arrive at a definitive diagnosis.
What are the possible Complications of Gestational Diabetes?
Most women with Gestational Diabetes deliver healthy babies. Women, in whom the blood sugar levels are not controlled, are at risk of developing medical problems, which may affect their child too. In such situations, there is an increased likelihood that the woman will need to have a C-section.
Complications for the mother may include:
- High blood pressure during pregnancy (pre-eclampsia or eclampsia): These are two serious pregnancy-related complications that can cause high blood pressure
- Pre-eclampsia is a condition of hypertension and high urine protein levels, during pregnancy
- Eclampsia is characterized by the appearance of seizures in addition to signs and symptoms of pre-eclampsia
- Increased likelihood of a miscarriage
- Future risk of diabetes: If a woman has Gestational Diabetes during one pregnancy, she is more likely to develop it again, in a future pregnancy. The woman is also more likely to develop diabetes - type 2, as she ages
Complications for the baby may include:
- Excessive birth weight: Extra glucose in the bloodstream crosses the placenta, causing the baby’s pancreas to produce an excess of insulin. As a result, the baby can grow to a large size (termed as macrosomia). Larger babies are more likely to become wedged in the birth canal, have birth injuries, or require a C-section for delivery
- Early (preterm) birth and respiratory distress syndrome: High blood glucose can increase the risk of early labor and delivery of the baby before the due date. Babies born prior to the due date may experience respiratory distress syndrome; a condition that causes breathing difficulties. The baby may need assistance to breath, until their lungs are fully mature
- Low blood sugar, or hypoglycemia, can develop in babies with mothers, who have Gestational Diabetes, because their insulin is being produced at a high level. Severe hypoglycemia can cause seizures in a baby. This may be treated by adequate breastfeeding and through intravenous glucose solutions, which have the potential to return a baby’s blood sugar back to normal levels
- Jaundice, a yellow discoloration of the skin and whites of eyes, may occur if the baby’s liver is not fully mature enough to break down bilirubin. Bilirubin is a substance formed, when the body recycles old red blood cells
- Type 2 diabetes (later in life): Children, who have mothers with Gestational Diabetes, inherently have a higher risk for developing obesity and type 2 diabetes, later in their lifetime
- Polycythemia, in which the baby suffers from high red blood cell mass
- Hypocalcemia, defined as having too low blood calcium levels, as well as hypomagnesemia, or low blood magnesium levels
- Birth defects, which may affect major organs, such as the brain or heart
- Shoulder dystocia, a situation in which the baby’s shoulders become trapped in the mother’s vagina, during vaginal delivery
- In severe cases, the baby may die, if the mother is not treated properly for the condition
How is Gestational Diabetes Treated?
The goal of Gestational Diabetes treatment is to keep blood glucose levels within normal ranges, during pregnancy, and for the growing baby to be healthy. Fetal monitoring should be performed often, to check the size and health of the baby.
- One of the manners to assess fetal heath is called a non-stress test. This is a painless, simple test for a pregnant mother and her baby. During this test, a machine that hears and displays the baby’s heartbeat, an electric fetal monitor, is placed on the abdomen
- Another method, called a biophysical profile (BPP), is a test that combines a non-stress test with an ultrasound study of the baby
- Using this method the physician can evaluate the baby’s heartbeat, movements, breathing, and muscle tone, determining if the baby is surrounded by an adequate amount of amniotic fluid
- Based upon a scoring system, the test helps determine BPP score. This baby’s score on this exam indicates if the baby is receiving enough oxygen, or not
- When amniotic fluid levels are lower and the baby is not urinating enough, it usually indicates that the placenta may not be working fully
- Fetal movement monitoring: In this method, fetal movement counting is performed to count, how often the baby kicks over a set period of time. Infrequent movements can be indicative that the baby is not receiving enough oxygen
- Women with Gestational Diabetes should monitor their diet, taking the following into consideration:
- Fats and proteins should be taken in moderation
- Carbohydrates in foods, such as fruits, vegetables, and complex carbohydrates, such as bread, cereal, pasta, and rice, should form part of the diet
- Sugars, such as fruit juices, soft drinks, and pastries, should be consumed in less amounts
- A professional dietician will help plan an optimal diet
- If careful management of one’s diet is not sufficient enough to control blood glucose levels, one may be prescribed oral diabetes medications or insulin therapy. Some physicians may prescribe oral blood sugar control medication, such as glyburide
- Breastfeeding the child can help achieve post-pregnancy weight goals and help prevent type 2 diabetes or avoid obesity, into the future
How can Gestational Diabetes be Prevented?
A few tips to help avoid or control Gestational Diabetes include:
- In overweight individuals, reducing body mass index (BMI) to a normal range, prior to pregnancy, decreases the risk of developing Gestational Diabetes
- Remain active and eat healthy during pregnancy, to help avoid any glucose intolerance. Choose foods, which are high in fiber, low in fat and calories. Focus on eating plenty of fruits, vegetables, and whole grains. Exercise for a period of 30 minutes (most days of the week), to help remain active
- Start prenatal care early on and have regular prenatal visits to improve health. Prenatal screenings, between weeks 24-28 of pregnancy, aids in early detection of Gestational Diabetes
What is the Prognosis of Gestational Diabetes? (Outcomes/Resolutions)
- A majority of the women with Gestational Diabetes have the ability to control their blood pressures and avoid any harm, either to themselves or to their baby. However, some of the women are at an increased risk of high blood pressures (eclampsia and pre-eclampsia)
- Women with Gestational Diabetes usually have larger babies at birth, increasing the chances of medical issues at the time of delivery. These medical issues may include:
- Birth injury to the baby and the mother
- Surgical complications, due to delivery by C-section; these are rare incidents, but possible
- The infant is expected to have periods of low blood sugar (hypoglycemia), during the first few days
- The mother’s high blood glucose levels often normalize, following delivery. Women with Gestational Diabetes should be closely monitored, post-delivery. Nevertheless, several such women develop diabetes, within 5-10 years after delivery
- Pregnant mothers with Gestational Diabetes also have an increased risk of death of the fetus (intrauterine fetal demise), which can be reduced by regularly monitoring blood sugar levels
Additional and Relevant Useful Information for Gestational Diabetes:
Type 2 diabetes is a chronic disease in which the blood contains high levels of glucose (sugar). The following article link will help you understand type 2 diabetes.
What are some Useful Resources for Additional Information?
References and Information Sources used for the Article:
http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0001898/ (accessed on 05/28/14)
http://www.mayoclinic.com/health/gestational-diabetes/DS00316 (accessed on 05/28/14)
http://www.uchospitals.edu/onlinelibrary/content=P01513 (accessed on 05/28/14)
http://www.babycenter.com/0_gestationaldiabetes_2058.c (accessed on 05/28/14)
http://www.diabetes.org/diabetes-basics/gestational/ (accessed on 05/28/14)
Helpful Peer-Reviewed Medical Articles:
Gordin, D., Groop, P. H., Teramo, K., & Kaaja, R. (2013). [Hypertensive pregnancy in diabetes--risk factors and influence on future life]. Duodecim, 129(9), 932-938.
Han, S., Crowther, C. A., Middleton, P., & Heatley, E. (2013). Different types of dietary advice for women with gestational diabetes mellitus. Cochrane Database Syst Rev, 3, CD009275. doi: 10.1002/14651858.CD009275.pub2
Oliveira, D., Pereira, J., & Fernandes, R. (2012). Metabolic alterations in pregnant women: gestational diabetes. J Pediatr Endocrinol Metab, 25(9-10), 835-842. doi: 10.1515/jpem-2012-0175
Vambergue, A. (2013). [Gestational diabetes: diagnosis, short and long term management]. Presse Med, 42(5), 893-899. doi: 10.1016/j.lpm.2013.02.316
Vandorsten, J. P., Dodson, W. C., Espeland, M. A., Grobman, W. A., Guise, J. M., Mercer, B. M., . . . Tita, A. T. (2013). NIH consensus development conference: diagnosing gestational diabetes mellitus. NIH Consens State Sci Statements, 29(1), 1-31.
Ware, J. (2015, June). Gestational Diabetes Experiences: Demonstrating the Link Between Better Data and Better Care. In 2015 CSTE Annual Conference. Cste.
Xiang, A. H., Black, M. H., Li, B. H., Martinez, M. P., Sacks, D. A., Lawrence, J. M., ... & Jacobsen, S. J. (2015). Racial and ethnic disparities in extremes of fetal growth after gestational diabetes mellitus. Diabetologia, 58(2), 272-281.
Bider-Canfield, Z., Martinez, M. P., Wang, X., Yu, W., Bautista, M. P., Brookey, J., ... & Xiang, A. H. (2016). Maternal obesity, gestational diabetes, breastfeeding and childhood overweight at age 2 years. Pediatric obesity.