The last thing pregnant women need is another thing to worry about, but four per cent of Canadian women will get gestational diabetes mellitus (GDM) during their pregnancy. The good news? The negative side effects are easy to control once GDM is diagnosed.
No one is immune to GDM, but there are certain groups that are at an elevated risk. Obesity plays the largest factor in the development of GDM, along with excess weight gain during pregnancy. “Obesity makes it more difficult for insulin to work,” says Denice Feig, an endocrinologist at the Leadership Sinai Centre for Diabetes at Mount Sinai Hospital, Toronto.
Age is also a factor. Gestational diabetes risks increase after 35 years of age.
As with Type I and II diabetes, genetics and ethnicity play a role. High risk populations include: Aboriginal, Hispanic, African and Asian. Other high risk groups include women with a previous history of GDM or delivery of a macrosomic (excessive birth weight) baby, a history of polycystic ovary syndrome, acanthosis nigricans (dark patches on the skin), and/or the use of corticosteroids.
The primary differences are that GDM is impaired glucose tolerance during pregnancy, and for 95 per cent of women their diabetes will go away immediately after giving birth.
“Pregnancy is a stress test for diabetes,” says Feig. The hormonal changes make it difficult for insulin to work at an optimal level. “If women have a [preexisting] defect in insulin metabolism, it will be more pronounced during pregnancy,” says Feig.
As far as treatment and risks, GDM is basically the same as Type II diabetes. The only difference is that because Type I and Type II diabetes are present in early pregnancy, there are additional risk factors such as increased risk of still birth and congenital anomalies that don’t exist with GDM.
Since GDM occurs later in the pregnancy – usually third trimester, the primary impact is over-nutrition to the baby resulting in excessive birth weight. This can cause risks to both mom and baby during delivery through excess trauma and higher likelihood of a cesarean section delivery.
After birth, the risks to baby include low blood sugar and excess levels of insulin, along with an increased risk of jaundice. There is also the potential for long-term glucose intolerance and obesity. “In utero programming has a very strong relation to increased fat cell production resulting in obesity in the teen years and later in life,” says Feig. The results of GDM may not start to show until your child reaches 10, 15 or even 20 years of age.
Women with multiple risk factors should be tested in the first trimester; then again in the second and third. All other women should take a blood screen test between 24 and 28 weeks.
“The screening is highly sensitive and picks up everyone who might have GDM,” says Feig. For that reason there are a lot of false positives that require a second, more involved test to confirm diagnosis.
Gestational diabetes is managed very similarly to Type II diabetes. Blood sugar levels need to be monitored and kept in check through diet and, possibly, insulin medication that is safe for pregnancy.
“Pay attention to how many carbohydrates and sugar you eat at one sitting,” says Feig. Avoid eating pasta, milk, bread, fruit and sugar in isolation. You should also limit high fat foods and focus on low Glycemic Index items. Exercise after eating helps decrease circulating sugar levels so Feig suggests going for a walk after a meal. “Even if it’s just 10 minutes, it can help,” says Feig.