Is it a sin for both wife and husband if contraception is used?
Contraception normally implies a consensual act, which means both spouses would be morally implicated. However, if one spouse sexually forces himself on the other and uses contraception in the process, the forced-upon spouse would not sin. If one spouse is coerced into contracepting, then the person who is coerced could likely have mitigating circumstances regarding his participation, and thus his subjective culpability could be diminished.
In 1997, the Pontifical Council for the Family issued a vademecum—Latin for “to accompany me"—on contraception that provides theological and pastoral guidelines for confessors to serve married couples struggling with the Church’s teaching on contraception. I discuss that matter—and possible related mitigating circumstances in some cases—in a larger article on “Serving the Divorced and Remarried Well." And I provide a link to the vademecum as well.
God inscribed in the marital act a bond between the unitive (love-giving) and procreative (life-giving) aspects. Deliberately thwarting this bond via contraception is immoral, because it undermines the sexual expression of marital love by a husband and wife, an expression of love which by its nature is open to the blessed fruit of new life (see further CCC 2368-70, 2366-72).
By Tom Nash