RSS feedWhen a pregnant woman who has never had diabetes before is found to have a high blood sugar level during pregnancy, she is said to have gestational diabetes. About 4% of all pregnant women are affected by gestational diabetes. The risk factors for gestational diabetes are older mothers, positive family history of diabetes, a high body mass index (BMI) and ethnicity. Gestational diabetes is more common in African-Americans, Hispanics, Asians and Native Americans. While we do not know the exact cause of gestational diabetes, we do know that the weight gained during pregnancy and the placental hormones do lead to insulin resistance. When the pancreas is unable to produce enough insulin during the pregnancy, blood glucose levels increase to abnormally high levels, thus giving rise to gestational diabetes.
The high glucose level in the mother’s blood leads to a high glucose level in the unborn fetus. This excess glucose leads to increased fat deposition in the infant, leading to a ‘fat’ baby (or macrosomia). As the fetus is much bigger than normal, vaginal delivery may be more difficult and injury to the shoulder of the baby during birth is more common. These babies are also at an increased risk of developing childhood obesity and type II diabetes as grown-ups. The mothers are also at increased risk of developing type II diabetes later on in life. Apart from this, is gestational diabetes associated with other conditions later in life?
A study carried out by US and Israeli researchers investigated the incidence of pancreatic cancer in a cohort of 37,926 women in Jerusalem who gave birth during the period 1964-1976 (BMC Med 2007; 5: 25). These women were followed up for 28 – 40 years. The study found that women who had gestational diabetes showed a relative risk of 7.1 for developing pancreatic cancer. The interval between the development of gestational diabetes and pancreatic cancer ranged from 14 to 35 years. There were no cases of pancreatic cancer in those women with type I diabetes. Using the same population, the same group of researchers also studied the relationship between gestational diabetes and breast cancer (Breast Cancer Res Treat 2007 May 3; Epub). Women who had had gestational diabetes and who were 50 years or older had a 50% increased chance of developing breast cancer. This increased risk was, however, not seen in those women who were < 50 years of age.
Gestational diabetes is becoming more common worldwide. No doubt this increased incidence is related to the increased incidence of obesity worldwide. Type II diabetes is more common in obese people and there is evidence that type II diabetics have an increased risk of developing pancreatic cancer. The association of gestational diabetes with pancreatic and breast cancers does not mean that all pregnant women with gestational diabetes will develop cancer. However, taking preventive measures is better than trying to find a cure. Hence, simple measures, such as not having a high BMI before getting pregnant and not putting on an excessive amount of weight during pregnancy, are just some of the things one can do to reduce the chance of developing gestational diabetes and the associated increased risk of developing cancer many years down the road.
