Gestational diabetes occurs during pregnancy and usually goes away after the baby is born. In pregnancy, the placenta makes hormones that help the baby to grow and develop. Gestational diabetes occurs because these hormones also block the action of the mother’s insulin on the body’s cells and stops them from being able to take up glucose (insulin resistance). To make up for these hormones blocking the insulin, the woman’s body needs more insulin than normal to get the glucose into the cells to be used as energy. In most pregnancies, a woman’s body can meet the extra demand for insulin, but if the body cannot produce this much insulin, gestational diabetes develops. When the pregnancy is over and pregnancy hormones are no longer blocking insulin from working, gestational diabetes no longer exists.
Up to 8% of all pregnant women will develop gestational diabetes around the 24th to 28th week of pregnancy. Those most at risk include women over thirty, those who have a family history of type 2 diabetes and those who are overweight.
Aboriginal and Torres Strait Islander women are at increased risk, as are certain ethnic groups including Indian, Vietnamese, Chinese, Middle Eastern and Polynesian/Melanesian women. Women diagnosed with gestational diabetes are at a higher risk of developing type 2 diabetes later in life.
AusDRisk - Type 2 Diabetes Risk Assessment Tool a risk factor calculator provides information about your risk of developing type 2 diabetes.
Gestational diabetes is diagnosed with an Oral Glucose Tolerance Test (OGTT). For more information, including how gestational diabetes may affect your baby, go to our information sheets.