An excellent summary of the benefits of Natural Family Planning can be found here.
-- Key Church documents on human sexuality, marriage, and family life:
- Familiaris consortio: The Role of the Christian Family in the Modern World
Pope John Paul II, 1980
- Humanae vitae: On the Regulation of Births
Pope Paul VI, 1968
- Casti connubii: On Christian Marriage
Pope Pius XI, 1930
-- Links to other helpful resources:
The Couple-to-Couple-League is an excellent organization that provides NFP resources, classes, and educational materials. They have affiliated local teaching couples throughout the country.
Contraception, Why Not by Dr. Janet Smith is the most persuasive presentation of the Church's teaching on artificial contraception I have come across. The first time I heard it, it really blew away any reservations or misunderstandings I had about the issue. Contraception, Why Not? is available here in CD format. I highly recommend it.
One More Soul is another excellent organization that has a variety of resources related to natural planning including and invaluable on-line directory of NFP only physicians.
My thoughts on the 42nd Anniversary of Pope Paul VI's prophetic encyclical Humanae Vitae which reaffirmed the Church's opposition to artificial contraception can be found here.