The way in which the body deals with sugar changes during pregnancy. Blood sugar levels are normally kept within a fairly narrow range due to the effects of insulin, a hormone produced by the pancreas. However, some of the hormones produced during pregnancy can impair insulin efficiency, resulting in the excretion of sugar in the urine, and some women may become temporarily diabetic (gestational diabetes). This type of diabetes is non-insulin-dependent and usually disappears within hours of birth. Insulin-dependent diabetes usually begins before the age of 30 and needs to be treated with injections of insulin. lf you have this type of diabetes, you should talk to a specialist before becoming pregnant. Very occasionally pregnancy reveals previously undiagnosed diabetes.