Contraception and Direct Sterilization
The Church teaches that it is necessary that each and every marriage act remain open to the procreation of human life. While spouses may have good reasons to space the births of their children, contraception and direct sterilization are unacceptable methods because they reject the deepest truth of our humanity. The ends do not justify the means. (cf. Catechism of the Catholic Church 2366, 2399)
Many forms of contraception (Pill, Plan B, IUD, NuvaRing, Yaz, Yasmin, Minipill, Patch, Depo-Provera, Norplant) at times prevent a living human embryo from attaching to the lining of the womb and he or she will die. This is a very early abortion.
Learn more about Natural Family Planning, which is 97-99% effective to avoid pregnancy and is also effective when used to achieve a pregnancy.