Pregestational hyperglycemia cause adverse effects on mothers and their offspring. We aimed to evaluate the maternal hyperglycemia influence on pre-embryos from diabetic rats and on their generations (daughters and granddaughters). Diabetes was induced in Sprague-Dawley rats. The mothers and their female pups were submitted to oral glucose tolerance test in adulthood. In day 4 of pregnancy, pre-embryos were collected for morphological analysis. The diabetic mother, daughter and granddaughter rats showed glucose intolerance and their pre-embryos presented developmental delay, degeneration and losses compared to the nondiabetic group. Thus, maternal diabetes transgenerationally affects embryos at early development, which contributes for embryofetal losses.