The incidence of gestational diabetes has recently been increasing. In Estonia, the prevalence rate exceeded 6%. On the one hand, the reason for the increase in prevalence is overweight among the population; on the other hand, the criteria for diagnosis are becoming more strict. Gestational diabetes can be accompanied by many adverse consequences (e.g. preeclampsia, macrosomia, risk of diabetes) for both mother and child, both during and after pregnancy. Due to the increased frequency of gestational diabetes, more women are counselled and treated when necessary, and the proportion of various adverse consequences (e.g. preeclampsia) has been reduced.