The Catholic Church is opposed to contraception on moral grounds, believing that all sexual acts must be open to the transmission of life. Although it approves the use of natural family planning (NFP) methods for those married couples with serious reasons for spacing or avoiding pregnancy, all artificial forms of contraception are prohibited. (Cf. Humanae Vitae)

There are individuals and groups who disagree with their movement's official teaching, however. For example, the quiverfull movement within Protestantism is morally opposed to all forms of family planning (including NFP), and the "Winnipeg Statement"

by the Canadian Catholic Bishops states their belief that Catholics can in good conscience use artificial contraception. In the U.S. the most well known Catholic alternative to official Catholic teaching about birth control is presented in the critical works of Charles E. Curran.

Islam

The Qur'an does not make any explicit statements about the morality of contraception, but contains statements encouraging procreation. Various interpretations have been set forth over time, and at the time of this writing, discussions on the web can be found easily that take various positions. Early Muslim literature discusses various contraceptive methods, and a study sponsored by the Egyptian government concluded that not only was azl (coitus interruptus) acceptable from a moral standpoint, but any similar method that did not produce sterility was also acceptable.

"It is permissible to use condoms so long as this does not cause any harm and so long as both husband and wife consent to their use, because this is similar to ‘azl (coitus interruptus or “withdrawal”). But it reduces the sensation of pleasure, which is the right of both partners, and reduces the chance of conception, which is also the right of both partners. Neither one of them is allowed to deprive the other of these rights. And Allaah is the course of strength."