Objective— To determine the prevalence of gestational diabetes mellitus in Zuni Indian women and the subsequent rate of diabetes among Zuni women with GDM.
Research Design and Methods— A retrospective analysis of 809 deliveries over a 4-yr period among Zuni Indian women was conducted to determine the prevalence of GDM and diabetes antedating pregnancy. A prospective case-control study of 47 full-blooded Zuni Indian women with GDM and 47 control subjects was performed to determine the progression to clinical diabetes in women with a first-time diagnosis of GDM. Cases with GDM delivered during a defined 8-yr period. The control group of Zuni women delivered during the same time period but had plasma glucose values <7.8 mM on the 1-h glucose screening test. Cases with GDM and control subjects were matched for age, body mass index, gravidity, and length of follow-up. All women were re-evaluated for diabetes up to 9 yr after the index pregnancy.
Results— Between 1987–1990, 116 cases of GDM and 8 cases of pre-existing diabetes were identified, giving a prevalence of maternal diabetes in pregnancy of 15.3%. At the time of follow-up, 14 of 47 (30%) women with GDM had developed diabetes after a mean of 4.8 yr compared with only 3 of 47 (6%) from the control group with an average of 5.5 yr follow-up.
Conclusions— GDM is prevalent among Zuni Indians and is associated with an increased risk of diabetes. Glucose tolerance after GDM may deteriorate at a greater rate in Native Americans than in other populations.
