In the majority of women with gestational diabetes mellitus (GDM), glucose tolerance normalizes shortly after pregnancy. Nevertheless, GDM is one of the strongest predictors of subsequent type 2 diabetes (T2DM), which will develop in around half of the women with previous GDM. The pathophysiological traits from pregnancies complicated by GDM, which can be found several years after birth, and how these traits may influence abnormal glucose tolerance later in life are described. GDM shares pathophysiological traits with T2DM and includes increased inflammatory response, altered incretin effect, and changes in the microbiota. Furthermore, common T2DM risk gene variants are also more common in women with GDM. In addition to diabetes and prediabetes, women with a history of GDM are at risk of cardiovascular disease including hypertension, dyslipidemia, and insulin resistance. Regular follow-up screening for hyperglycemia is recommended in women with previous GDM, but the cost - benefit of this is not fully known. A healthy lifestyle is generally recommended, based on common sense and a few long-term intervention studies.