Sceening is Key for Women with Gestational Diabetes Mellitus (GDM)

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Trends in postpartum diabetes screening and subsequent diabetes and impaired fasting glucose among women with histories of gestational diabetes mellitus, by Assiamira Ferrara and colleagues. Diabetes Care 32:269–274, 2009

What is the problem and what is known about it so far?

Gestational diabetes mellitus (GDM) is high blood glucose that starts during pregnancy in women who have never had diabetes. GDM usually goes away after pregnancy, but women who have had GDM are likely to have it again in later pregnancies. Sometimes, women who seem to have developed GDM really have diabetes that just began to appear during their pregnancy; these women need continuing diabetes treatment after they give birth. Many women who have GDM go on to get type 2 diabetes later on. Losing extra weight, making healthy food choices, and getting exercise can help women who have had GDM avoid developing type 2 diabetes. Screening women who have had GDM for diabetes after they give birth can tell which women need continued diabetes care and which may be at risk for developing diabetes later.

Why did the researchers do this particular study?

The researchers wanted to look at current trends in screening women with GDM after birth and how well the screenings help to find women in need of further care.

Who was studied?

The study included nearly 14,500 women who had GDM between 1995 and 2006 through a large California health care system that included 17 hospitals and 23 clinics.

How was the study done?

The researchers found participants through the health system's GDM registry. They looked in health records to find out how many women had diabetes screening tests after their pregnancies and how many women with diabetes or pre-diabetes (blood glucose higher than normal but not high enough to be diagnosed as diabetes) were found as a result of the screenings. They also looked for characteristics of women who did or didn't have a screening.

What did the researchers find?

Between 1995 and 2006, the number of women each year who had screenings increased from less than one-fourth to more than one-half. Women who were older, of Asian or Hispanic background, had higher education levels, were diagnosed with GDM earlier, used diabetes medicines during pregnancy, and had more contacts with their doctors after their pregnancies were more likely to be screened. Women who were very overweight or had given birth more often were less likely to be screened, even though they were at higher risk for diabetes. For women who were screened, the type of screening test made a difference. An oral glucose tolerance test (OGTT) was more likely to identify women with diabetes or pre-diabetes than a fasting plasma glucose (FPG) test.

What were the limitations of the study?

The researchers could not learn the reasons why some women weren't screened after their pregnancies, which would be helpful for efforts to improve the number of women receiving screenings. The method used to tell if someone was very overweight may have resulted in some patients being wrongly classified. Information about other factors, such as women's family history of diabetes, was not available and may have shed more light on why they did or did not receive screenings.

What are the implications of the study?

Although diabetes screenings have increased over the years for women who have had GDM, they are still not performed as often as they should be. Women who have had GDM should be screened for diabetes after their pregnancy, and the OGTT may be a better test than the FPG for these high-risk patients.

FOR MORE INFORMATION

Gestational Diabetes

Diabetes and Pregnancy

Gestational Diabetes: What to Expect