Maturity-onset diabetes of the young (MODY) is a group of hereditary monogenetic forms of diabetes. MODY accounts for 1-3% of all persons with diabetes but is often undiagnosed or misdiagnosed as type 1 diabetes, type 2 diabetes, or gestational diabetes. Diagnosing MODY is essential, as the most optimal treatment both during and outside of pregnancy depends on the MODY type. This review focuses on the outcome and treatment of the three most common types of MODY during pregnancy.