Gestational Diabetes Ups Risk of Type 2
Study Shows Gestational Diabetes Raises Risk for Type 2 Diabetes by 19%
July 28, 2008 -- Nearly 19% of women who develop gestational diabetes during pregnancy are likely to develop
type 2 diabetes after
pregnancy, according to a new study.
Researchers say it's understood that gestational diabetes is a risk factor for
type 2 diabetes, but until now the magnitude of that risk was unclear.
"In this large, population-based study, we found that diabetes developed
within 9 years after the index pregnancy in 18.9% of women with previous
gestational diabetes; this rate was much higher than the rate among women
without gestational diabetes (2%)," write researcher Denice Feig, MD, of
the University of Toronto and colleagues in the Canadian Medical Association
(Have you been diagnosed
with gestational diabetes? Does this run in your family? Talk about it on
WebMD's Pregnancy: 2nd Trimester board.)
Gestational Diabetes Risks
The study followed 659,164 pregnant women in Canada who did not have a
history of diabetes prior to pregnancy. Of these, 21,823 developed gestational
diabetes during pregnancy.
Researchers found the rate of gestational diabetes rose during the nine-year
study period form 3.2% in 1995 to 3.6% in 2001.
Meanwhile, the number of women who developed type 2 diabetes after a
diagnosis of gestational diabetes rose from 3.7% at nine months after delivery
to 18.9% nine years after delivery.
Thanks to its size, researchers say this study allows them to make a more
robust estimate of the risk of developing type 2 diabetes after gestational
diabetes than in previous studies.
However, they point out that the study did not "assess the effect of
ethnicity, obesity and level of fasting glucose during
pregnancy, risk factors that are clearly associated with the development of
Nevertheless, researchers say this risk estimate should be used by health
care professionals in counseling pregnant women and targeting those women at
risk for type 2 diabetes for screening and prevention programs.