Gestational Diabetes

Also known as: Gestational Diabetes Mellitus (GDM), Pregnancy Diabetes

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Gestational diabetes, also known as gestational diabetes mellitus (GDM), is a medical condition that some women develop during pregnancy (gestation). The condition is associated with having higher than normal blood sugar level that usually shows up between the 24th and 28th weeks of pregnancy.

Similarly to other types of diabetes, gestational diabetes occurs when the cells in your body are unable to process insulin normally and your body becomes insulin resistant. Insulin is a hormone produced by pancreas that your body needs to help glucose (sugar) get from your blood into your body’s cells to make energy. During pregnancy, your placenta produces large amount of hormones that are necessary to sustain your pregnancy, but also cause sugar to build up in your blood. Normally, insulin takes care of the situation, helping sugar to get into your body cells. However, if pancreas does not produce enough insulin or your body cells stop absorbing insulin properly, the level of sugar in your blood rises, which triggers development of gestational diabetes that may affect your pregnancy and the health of your baby as well.

Although in most cases women with gestational diabetes do not have any symptoms of the disease, there is a number of risk factors for gestational diabetes. Women, who do not have those factors, can also develop gestational diabetes, but women, who do have one or more of the risk factors, have a higher chance of getting gestational diabetes. The risk factors include: having a family history of diabetes, being overweight during pregnancy or before, having high blood pressure, being diagnosed with gestational diabetes in the past, having prediabetes, previously having a baby over 9 pounds, expecting more than one baby, having PCOS (polycystic ovary syndrome), being physically inactive, and having a history of heart disease.

Having gestational diabetes does not necessarily mean that you had diabetes before getting pregnant or that you will continue having diabetes after pregnancy, but it is still a risk factor for developing type 2 diabetes later in life. Besides, if gestational diabetes is left unattended or poorly managed, it can also raise your child’s risk of developing diabetes and increase the risk of complications for you and your baby during pregnancy and childbirth, including stillbirth, birth trauma, labor difficulties, cesarean delivery, heavy post-delivery bleeding, and severe vaginal tear. That is why it is important to diagnose and treat gestational diabetes as early as possible.

Gestational diabetes is diagnosed with two tests. Sometimes, doctors start with glucose challenge test that involves drinking a sugar solution followed by a blood test in an hour. If the test result is unsatisfactory, your doctor might perform Oral Glucose Tolerance test (OGTT), when blood sugar is measured two hours after you drink an even sweeter glucose solution than the one provided for glucose challenge test. In some cases, doctors only perform Oral Glucose Tolerance test. This test can be done with and without prior fasting.

If you have been diagnosed with gestational diabetes, you should address it as soon as possible to bring your blood sugar level under control, keep your baby and yourself in good health during pregnancy and delivery, and avoid potential complications associated with gestational diabetes. This can be achieved by maintaining a healthy, low-sugar diet and by incorporating exercise in your daily routine because your body uses more glucose when you exercise, naturally lowering your blood sugar. In some cases, insulin injections might also be needed to control blood sugar during pregnancy.