What is my chance of having twins again?

I have a set of fraternal twins. I am 27 years old and 30 pounds over weight. Me and my husband have been discussing getting pregnant again and wanted to know our chances of having twins again (percentage wise). Twins run on my mother's side of the family. My great grandmother had a set of twins and it skipped 2 generations. I have 2 cousins who have had twins also. What is my percentage in having twins again?