Increasing prevalence of gestational diabetes mellitus (GDM) over time and by birth cohort: Kaiser Permanente of Colorado GDM Screening Program.

OBJECTIVE The prevalence of gestational diabetes mellitus (GDM) varies in direct proportion with the prevalence of type 2 diabetes in a given population or ethnic group. Given that the number of people with diabetes worldwide is expected to increase at record levels through 2030, we examined temporal trends in GDM among diverse ethnic groups. RESEARCH DESIGN AND METHODS Kaiser Permanente of Colorado (KPCO) has used a standard protocol to universally screen for GDM since 1994. This report is based on 36,403 KPCO singleton pregnancies occurring between 1994 and 2002 and examines trends in GDM prevalence among women with diverse ethnic backgrounds. RESULTS The prevalence of GDM among KPCO members doubled from 1994 to 2002 (2.1-4.1%, P < 0.001), with significant increases in all racial/ethnic groups. In logistic regression, year of diagnosis (odds ratio [OR] and 95% CI per 1 year = 1.12 [1.09-1.14]), mother's age (OR per 5 years = 1.7 [1.6-1.8]) and ethnicity other than non-Hispanic white (OR = 2.1 [1.9-2.4]) were all significantly associated with GDM. Birth year remained significant (OR = 1.06, P = 0.006), even after adjusting for prior GDM history. CONCLUSIONS This study shows that the prevalence of GDM is increasing in a universally screened multiethnic population. The increasing GDM prevalence suggests that the vicious cycle of diabetes in pregnancy initially described among Pima Indians may also be occurring among other U.S. ethnic groups.