Established preexisting diabetes affects over 1% of pregnancies, and that number is expected to rise. Hyperglycemia during the first few weeks of pregnancy can result in congenital malformations or miscarriage. Preexisting diabetes increases the risk of developing both fetal and maternal complications in pregnancy; some of which can be devastating. Through careful attention to contraception, preconception counseling and preconception medical care, many of these complications can be avoided. Preconception care (PCC) programs have been shown to be efficacious at reducing complications and perinatal mortality as well as cost effective. Wider adoption of PCC programs is needed.