Is a pregnant woman with diabetes more likely to give birth to a child with high birth weight?

Yes. Make sure that the diabetes is under good control. Dr thornalley in england has shown that diabetics become short of vitamin b1. All diabetics should be getting this as a supplement in large doses. See a nutritionist familiar with this research.
Usually. The typical diabetic usually has blood sugars above normal. The fetus is exposed to these levels and that causes predictable changes. If control is good and sugar levels normal, the size can be normal. Since the baby makes it's own insulin, it takes all the excess and stores it. Organs are over-sized and fat layers thick.

Related Questions

Is a pregnant woman with type 1 diabetes more likely to give birth to a child with high or low birth weight?

Usually high but... If a pregnant woman has had a poorly controlled diabetes for long period of time, she is more likely to have a newborn with low birth weight.
Depends on control. If blood sugar control isn't good, the pregnancy can be adversely affected and lead to fetal defects and prematurity, let alone potential loss of pregnancy. On the other hand, chronically elevated blood sugars can also make the baby too large. Higher risk for c-section and problems with delivery and newborn trouble regulating blood sugar. Please be safe for you and baby and take care of diabetes.