Abstract We aimed to investigate the association of
recreational physical activity before pregnancy with gestational
diabetes mellitus (GDM). A cross-sectional study
was performed using self-reported data from the Pregnancy
Risk Assessment and Monitoring System. The study population
included 1,052 self-reported GDM cases and
10,351 non-GDM controls. Recreational physical activity
in the 3 months before pregnancy was recalled in postpartum
structured interviews. Compared to women exercising
less than 1 day per week, women who exercised
[5 days per week in the 3 months before pregnancy had a
31% lower odds of GDM (adjusted odds ratio [aOR]: 0.69;
95% confidence interval [CI]: 0.46, 1.03). Women who
exercised 1–4 days per week had a 7% lower odds of GDM
(aOR: 0.93; 95%CI: 0.72, 1.19). We did not observe statistically
significant associations between pre-pregnancy
physical activity and GDM risk. However, the magnitude
and direction of association are consistent with previous
observational studies. These studies collectively