Introduction - Gestational Diabetes Mellitus (GDM)
This section is aimed at helping health care professionals who care for women diagnosed with gestational diabetes mellitus. The tips for managing glucose levels are very similar to those for women with Type 1 or Type 2 Diabetes, so this section will be helpful for these mothers too. The tips are meant to be practical and succinct, so that you can use them in your consultation. They are well matched to the Patients’ section and resources on this website.
If you are looking for deeper explanations for each topic, links and resources are provided.
Diagnosis
Screening for Gestational Diabetes Mellitus (GDM) is recommended for all pregnant women, using the oral glucose tolerance test. The glucose challenge test is no longer recommended. The timing of the OGTT depends on the woman’s risk for GDM:
GDM predicts that the woman has a higher risk of developing type 2 diabetes in the future. So, learning about GDM and about the healthy day-to-day habits that keep it under control is an important chance for her to prevent diabetes in her life.
Risk factors for GDM
Oral glucose tolerance test (OGTT)
The 75-gram oral glucose tolerance test (OGTT) is used to screen and diagnose GDM. The glucose challenge test (GCT) is no longer recommended.
How to prepare for the oral glucose tolerance test (OGTT):
The OGTT result may be misleading when:
In these cases, the 1-hour and 2-hour results may be falsely elevated. If she vomits the glucose drink, the post-dose results will be falsely normal or low. The options for diagnosis are;
When to perform the Oral glucose tolerance test (OGTT):
Alternatives to the Oral glucose tolerance test (OGTT)
If women refuse to have an OGTT, she was unable to complete it or if the result is uncertain, there are alternative pathways to diagnosing GDM. None of these are as accurate as the OGTT, so the results need to be considered carefully:
Post-partum Oral glucose tolerance test (OGTT) and risk of Type 2 Diabetes
After delivery, women with GDM are at a higher risk of developing Type 2 Diabetes. The recommendations for post-partum OGTT screening are:
The 10-year risk of developing type 2 diabetes is 50 – 70%. This risk is reduced by: