The way the body handles sugar changes in pregnancy. About 5-10% of pregnant women who do not have pre-existing diabetes will develop higher than normal blood sugars by around 28 weeks’ gestation. These women have gestational diabetes – GDM. The condition goes away after pregnancy but may recur in subsequent pregnancies. There are also some longer-term implications for your health if you have had a pregnancy affected by GDM. We know, for instance, that you are more at risk of developing Type 2 diabetes in the future if you have had GDM.
Certain women are more at risk of developing GDM. Your risk increases if you:
- Are over 30 years of age
- Are having a twin or multiple pregnancy
- Have a family history of Type 2 diabetes
- Are overweight
- Have had GDM in a previous pregnancy
- Are of Aboriginal or Torres Strait Islander background
We organise screening for all pregnant women for GDM at 26-28 weeks’ gestation. If you have particular risk factors you may have screening at an earlier stage. Screening involves testing your blood sugar after you taking a measured sugar drink.
If your screening test shows that you have GDM you will be referred to a specialist diabetic education nurse who will advise you on diet and blood sugar monitoring. We usually manage GDM by dietary modification alone. Some women may need tablets (metformin) to control their blood sugar levels and others may need insulin injections. If you need insulin for your GDM you will be referred to a physician who has an interest in diabetes.
If you have GDM we need to monitor the growth of your baby as well. Sometimes your baby can be larger than expected and Dr Etherington will take this into consideration when planning your delivery.
Provided you have no other problems in your pregnancy it should still be possible for you to have a normal delivery if you have GDM. However we do not let women with GDM go beyond their expected due date, so the chance of needing induction of labour increases. If you need to have insulin to control your blood sugars Dr Etherington usually advises delivery up to 2 weeks before your due date.
You can get more useful information from the Diabetes Australia website.