Can you get endometriosis on the pill?

Sort of. If you look up the theory of "muellerianosis" - this indicates that endometriosis is laid down during the early embryo development and awaits stimulation when that woman starts her periods. Some women with endometriosis feel pain right from the start of their peiords, and some later. Being on the pill can delay when a woman with endo might start feeling it but it does not cause endo.