In reply to Dave the Rave:
There's many reasons for girls 15 and under to be on the pill.
It helps regulate thier cycle
It reduces the heaviness of a bleed
It reduces pain during bleeds
It helps reduce embarrassing acne
Birth control obviously
There are a lot of young girls on the pill for any range of reasons.
Also if they want to have sex they will, whether on the pill or not. sad fact but true. If they are going to have sex anyway are they not better having extra protection?