The Vatican approves the rhythm method for birth control in 1930.
The Catholic church has a history of restricting birth control. They taught that sex was to be used for procreation and should not be restricted. Even with approving the rhythm method, they emphasized the procreation of sex.
This method is now called family planning. People use the menstrual cycle to decide when to have sex. When they want children they have relations during peak fertility times. Otherwise, they avoid peak fertility times to avoid pregnancy. Today some people of the Catholic church encourage birth control methods while others still say to avoid all birth control.