In some of the best transformation scenes in all media, the gigantic size increase or the tremendous speed of the TF process may render the character completely naked. Their clothes are ripped into small shreds flung a great distance.
These are not poof transformations, where a magical flash or pink smoke merely hides the replacement process, but a growth spurt too rapid to follow with the human eye. It goes directly to the unclothed aftermath. For example if a girl were to grow into a woman in less than a second, leaving a nude woman standing there while pieces of cloth tumble down from the ceiling.
This type of explosive growth seems to be very common in "were" animal transformations, like the werewolves from Twilight.
More humanoid examples include the Incredible Hulk, were he often expands to giant size between panels or offscreen.
In the Tv series "Misfits of Science", Dr. Elvin Lincoln had the ability to shrink for a limited time to doll-size via hormonal treatments. Then he had to put on tiny clothes he carried with him, which often disappeared when he returned to normal.
When Ant-Man's 13 y.o. daughter Cassie Lang expands to giant size, whatever clothes she is wearing are instantly obliterated.
Regarding Male Age Progression, Yuki Hiro was seen exploding out of his school uniform. The Female AP scenes were much less destructive though.
In the "Sabrina the Teenage Witch" episode "The true adventures of Rudy Kazootie", the clothed baby's growth into a nude man happened completely offscreen.
There are very few visual depictions of this type of process involving female AP.
