The Catholic church and other church approved methods of birth control are not effective. The Catholic church is very limited with the amount and different ways of approved birth control, and by limiting the way birth control should be practiced automatically makes is inferior to other ways and less effective.
Any limitation of healthy birth control has negative consequences. The Catholic Church's contraception policy eliminates a lot of options for its churches members. When the Catholic Church was created birth control was simply abstinence. For a church which is not a scientific community by nature to assume its birth control can perform equally to that of all of the intelligent minds of the world is foolhardy.