Gestational Diabetes: What You Need To Know

Gestational diabetes is a form of elevated blood glucose that occurs only during pregnancy. Since it only occurs during pregnancy women, but not men, can develop the condition that typically resolves itself after the child is born. However, having gestational diabetes increases the woman’s risk of developing type 2 diabetes in her lifetime as well as increasing the child’s risk of developing type 2 diabetes over his or her lifetime. Increased risk of pre-eclampsia, a serious pregnancy complication, is seen in women with gestational diabetes, as is a higher rate of delivery by caesarian section.

A Definition of Gestational Diabetes

As with all types of diabetes, gestational diabetes occurs because of high blood glucose levels. Women that are diagnosed with gestational diabetes are patients that have not already been diagnosed with type 1 or type 2 diabetes before getting pregnant. The rate of diagnosis of gestational diabetes is approximately 3-10% of the population of expecting mothers and is most commonly associated with increased age, ethnicity, and medical and weight factors.

Insulin resistance in the mother’s body is thought to be triggered by the increased hormone levels during pregnancy, particularly in the second and third trimester. The theory is that this may be an overreaction of the body in an attempt to make glucose accessible to the fetus, with a natural insulin resistance occurring in the second trimester of a healthy pregnancy.

In women that are diagnosed with gestational diabetes the insulin resistance is more significant and high levels of glucose can pose health problems for both the mother and the baby. Healthy diet, exercise and safe weight maintenance during pregnancy can help to mitigate the effects of gestational diabetes and reduce any ongoing risks that remain after the pregnancy ends.

Risk Factors for Gestational Diabetes

Any woman can be at risk for developing gestational diabetes, although in the vast majority of cases there are clear risk factors present. One major factor for women to consider is whether there is a history of type 2 diabetes in the family and particularly in a first degree family member.  A diagnosis of type 2 diabetes in a mother, father, sister, brother or child may indicate a pregnant woman might be at higher risk of developing gestational diabetes. Women that have been diagnosed with prediabetes, metabolic syndrome or have had gestational diabetes during a previous pregnancy are at higher risk for gestational diabetes during subsequent pregnancies.

Abnormal glucose values are seen as a key risk factor for doctors to consider. Since many pregnant women have few if any symptoms, routine blood testing using oral glucose tolerance test is seen as critical. It is also seen as essential in studies to use the most stringent universal test criteria to avoid under diagnosis of some at-risk women. 1

Risk factors also include obesity. Women with a pre-pregnancy BMI (Body Mass Index) that indicates they were overweight, moderately obese or morbidly obese have 1.97, 3.01 and 5.55 odds ratios of developing gestational diabetes over women with normal BMI. Underweight women had a 0.75 odds ratio of developing gestational diabetes compared to normal BMI subjects. The same study which included records from 671,945 women over 30 years also showed that for each 1 kg m-2 increase in BMI there was an increased prevalence of gestational diabetes of 0.92%. 2

Age is yet another factor with women 25 to 35 years old demonstrating a much higher prevalence of gestational diabetes. Women of non-white ethnic backgrounds are also at higher risk although the specific reasons as to why race is a factor are not clearly understood.

Symptoms of Gestational Diabetes

Most women with gestational diabetes will have few if any symptoms. It is important to talk to your doctor about pregnancy planning and achieving a normal BMI prior to pregnancy. If you are pregnant and have an above average BMI it is essential to have regular blood glucose tests and report any changes in thirst, hunger, or urination volume or frequency. Identifying these changes as symptoms of gestational diabetes can be difficult for many women as these are typically physical changes that are associated with the pregnancy itself.

Women that have any risk factors for gestational diabetes, particularly a history of prediabetes or gestational diabetes and a family history of gestational diabetes should talk to their doctor about regular testing. If necessary, insulin treatment, diet and exercise may be considered an essential part of the pregnancy plan.

Treatment of Gestational Diabetes

Treatment of gestational diabetes is often managed through diet and exercise. This may require that a women with any of the risk factors discussed start regular blood glucose testing using a home monitor. This is a simple blood test using a blood glucose meter several times a day. If abnormalities in blood glucose levels are noted early then intervention provides the best options to avoid any complications. It will also be important to continue to regularly test your blood sugar after the delivery and up to six weeks after birth of the child.

Women that have gestational diabetes have a higher risk of developing type 2 diabetes later in life. Key factors in comprehensive literature review studies indicate that several factors pose a higher risk. The research indicates that family history of diabetes, the use of insulin during pregnancy, and development of gestational diabetes early in the pregnancy as having the greatest predictive value in the later development of type 2 diabetes.3

In another study it was found that women that had a history of gestational diabetes also had increased risk of other health complications besides the development of type 2 diabetes. This study of women between the ages of 27 and 49 found that women with gestational diabetes compared to same age women that gave birth without gestational diabetes had a higher risk of developing cardiovascular disease, which is closely linked to the development of type 2 diabetes. 4

Women that are planning on becoming pregnant need to consult with their doctors and develop a pre-pregnancy plan to reduce the risk of developing gestational diabetes. Those women with risk factors for gestational diabetes, particularly a family or personal history of gestational diabetes or type 2 diabetes need to follow a healthy eating plan, make good diet choices and get regular safe exercise during pregnancy to minimize their risk of developing gestational diabetes.

References

1 Kautzky-Willer, A., Bancher-Todesca, D., Weitgasser, R., et al.  (2008). The Impact of Risk Factors and More Stringent Diagnostic Criteria of Gestational Diabetes on Outcomes in Central European Women . The Journal of Clincial Endocrinology & Metabolism , 1689-1695.

2 Torloni, M. R., Betran, A. P., Horta, B. L., et al. (2009). Prepregnancy BMI and the risk of gestational diabetes: a systematic review of the literature with meta-analysis. Obesity Reviews , 194-203.

3 Baptiste-Roberts, K., Barone, B. B., Gary, T. L., et al. (2009). Risk Factors for Type 2 Diabetes Among Women with Gestational Diabetes: A Systematic Review. The American Journal of Medicine , 207-214.

4 Shah, B. R., Retnakaran, R., & Booth, G. (2008). Increased Risk of Cardiovascular Disease in Young Women Following Gestational Diabetes Mellitus . Diabetes Care , 1668-1669.

This article was originally published July 12, 2012 and last revision and update of it was 9/10/2015.