Everyone knows that millions of Catholic married couples are using contraceptives irrespective of the Church’s condemnation of the practice. What is interesting about this reality is that the common methods being used place the responsibility on either the man or the woman, but not both. This means that only one of the two is actively facilitating contraception. So, for example, what if a Catholic man has a change of heart on moral grounds and would rather his wife switch from the pill to natural family planning and she refuses? According to Pope Pius XI, he would not be culpable for the sin of contraception:
“Holy Church knows well that not infrequently one of the parties is sinned against rather than sinning, when for a grave cause he or she reluctantly allows the perversion of the right order [contraception]. In such a case, there is no sin, provided that, mindful of the law of charity, he or she does not neglect to seek to dissuade and to deter the partner from sin” (Casti Connubii, 1930, #59).