In Brazil, in 2010, the prevalence of GDM in women aged over 20 years old attended in the Uni ed Health System (SUS) was 7.6%(5). One study for determining the prevalence of GDM in pregnancies attended in Primary Healthcare Centers in the city of Vitória in the Brazilian state of Espírito Santo (ES) concluded that this rate was 5.8%, in a sample of 396 pregnant women(6). A separate study undertaken in Pelotas in the Brazilian state of Río Grande do Sul (RS), which investigated the factors associated with the occurrence of GDM in 4243 puerperas, concluded that the prevalence of this pathology was of 2.95%(7).