Abstract Objectives: The authors hypothesized that women with a history of gestational diabetes mellitus (GDM) during pregnancy would exhibit more severe periodontal disease than controls without a history of diabetes during pregnancy. Methods: Data from NHANES III provided information for 4,244 women ages 20–59. One hundred and thirteen had a history of GDM (GDM+), while 4,131 had no history of diabetes before or during their pregnancies (GDM‐). Women were further classified by the presence or absence of diabetes mellitus (DM+ or OM‐) at the time of their NHANES 111 examination. Periodontal disease (PO) was defined as one or more teeth with one or more sites with probing depth ≤4mm, loss of affachment ≤2mm, and bleeding on probing. Results: The PD prevalence among women who were GDM+DM‐ was 9.0% and 4.8% for those who were GDM‐DM‐. PD prevalence for women who were GDM+DM+ was 30.5% and 11.6% for GDM‐DM+ subjects, respectively. A logistic regression model, controlling for age, calculus, smoking, and income estimated women who were GDM+DM+ were more likely to have periodontal disease than women who were GDM‐DM‐ and women who were GDM‐DM+. The GDM+DM‐ group also tended to be more likely to have PD than the GDM‐DM‐ and GDM‐DM+ groups. However, the odds ratios were not statistically significant. Conclusions: These results support the hypothesis that women with gestational diabetes mellitus (GDM) during pregnancy may be at greater risk for developing more severe periodontal disease than pregnant women without GDM.