android – Should I preload interstitial apps when my game starts?

I just recently added interstitial ads to my game. I loaded my interstitial ads when the main game actually starts so it wouldn’t take long to load after the user exits to the menu, but on profiling the memory usage, I realized that there are a lot of ad related allocations that are causing the gc to run wild. Is it that I should only request ads when I need them?