Yes you are right about Pope John XXIII starting the Commission. He died and then Pope Paul VI resumed it. It would not surprise me that Catholics did start to use it in the 50s but if I recall correctly the Pill came out in 1959.
In 1941, progesterone was first made from wild Mexican yams.
In 1945, a Harvard endocrinologist wrote about the possible use about birth control through hormone therapy.
In 1951 in a lab in Mexico City, the first orally effective form of progesterone was created.
In 1952, contraceptive chemiclas were shown to work when tested on women (as in, regulating their cycle).
In 1954 the first human trials were approved by the FDA.
By 1955, it had been shown conclusively from the tests that it stopped ovulation.
In 1956, Enovid was made, and in an article in Science magazinein Novemeber of 1955, the information was made widely public about it’s use and effectiveness.
In 1957 Enovid was approved for treatment of sever menstrual disorders, with the note that it would prohibit ovulation (this may sound odd, but most states still had laws preventing the sale of contracpetives; and some, if not a large part of the research had been directed towards treating menstrual disorders).
In 1959, President Eisenhower stated that birth control was not the governemnt’s business.
By late 1959, over 500,000 women were using the Pill. It was touted as simply extending the safe period.
By 1962 1.2 million women were using it in the US.
By 1963, 2.3 million women were using the Pill.
By 1964, 25% of married couples were using it.
In 1965, 6.5 million women were using it in America.
By 1967, 12.5 million users were estimated world wide.
In 1968 Humanae Vitae was issued.
By 1970, and estimated 2/3s of all Catholic women were using some form of birth control, with 28% using the Pill.
By 1973, 10 million women were using the Pill in the US.
By the 1980’s, and estimated 80% of Catholic women were using the Pill, among its variations.