What Does the Catholic Church Teach About Sex? Marriage, Contraception and Chastity

The Catholic Church teaches that sex belongs only in marriage between a man and a woman, where it has two meanings that may not be separated: it unites husband and wife, and it stays open to new life. Its teachings on contraception, sex before marriage and same-sex relations all follow from that one.

The Church asks everyone, married or single, to live chastely, and it lets a married couple space births for a just reason by natural family planning, which works with the woman’s infertile days instead of preventing conception. Many Catholics disagree with parts of this teaching: in a Pew Research Center survey of February 2025, 84 percent of U.S. Catholics said the Church should allow birth control, though Pew noted that its question did not separate natural methods from contraception.

Why does the Church say sex has two meanings?

The Catechism of the Catholic Church, the Church’s official summary of its teaching, puts it in two sentences: “The spouses’ union achieves the twofold end of marriage: the good of the spouses themselves and the transmission of life. These two meanings or values of marriage cannot be separated without altering the couple’s spiritual life and compromising the goods of marriage and the future of the family” (Catechism 2363).

The Catechism roots both meanings in Genesis (2331, 2335). “So God created man in his own image, in the image of God created he him; male and female created he them. And God blessed them, and God said unto them, Be fruitful, and multiply” (Genesis 1:27–28). The next chapter gives the union: “Therefore shall a man leave his father and his mother, and shall cleave unto his wife: and they shall be one flesh” (Genesis 2:24). When Jesus was asked about divorce, he quoted that verse and added, “What therefore God hath joined together, let not man put asunder” (Matthew 19:5–6).

Pope Paul VI set out the teaching in his 1968 encyclical Humanae Vitae. It rests, he wrote, “on the inseparable connection, established by God, which man on his own initiative may not break, between the unitive significance and the procreative significance which are both inherent to the marriage act” (Humanae Vitae 12). The unitive meaning is the union of the couple; the procreative meaning is the act’s openness to a child.

Openness to life does not require that every act could conceive a child. Married intercourse “does not, moreover, cease to be legitimate even when, for reasons independent of their will, it is foreseen to be infertile” (Humanae Vitae 11). A couple past the age of childbearing, or a couple who cannot have children, does nothing wrong by making love. What the Church rules out is a deliberate act that takes that possibility away. Paul VI also wrote that sex imposed on a spouse is not an act of love: “a conjugal act imposed on one’s partner without regard to his or her condition or personal and reasonable wishes in the matter, is no true act of love” (Humanae Vitae 13).

Is sex a sin in Catholic teaching?

No. Inside marriage the Church calls it good. The Catechism, quoting the Second Vatican Council, calls the acts of married love “noble and honorable,” says that “sexuality is a source of joy and pleasure,” and quotes Pope Pius XII, speaking in 1951: “The Creator himself . . . established that in the [generative] function, spouses should experience pleasure and enjoyment of body and spirit. Therefore, the spouses do nothing evil in seeking this pleasure and enjoyment. They accept what the Creator has intended for them. At the same time, spouses should know how to keep themselves within the limits of just moderation” (Catechism 2362).

Paul treats sex in marriage as something husband and wife owe each other: “Let the husband render unto the wife due benevolence: and likewise also the wife unto the husband.” He allows a pause only by agreement: “Defraud ye not one the other, except it be with consent for a time, that ye may give yourselves to fasting and prayer; and come together again” (1 Corinthians 7:3, 5). “Due benevolence” is the King James phrase for what each spouse owes the other.

For engaged couples of any church, Whom God Has Joined is a marriage-preparation course of fifteen lessons, one of them on sex, and its first lesson is free to read.

Why does the Church forbid contraception?

Because contraception separates the two meanings that the Church holds God joined. Humanae Vitae excludes “direct sterilization, whether of the man or of the woman, whether permanent or temporary,” and “any action which either before, at the moment of, or after sexual intercourse, is specifically intended to prevent procreation—whether as an end or as a means” (Humanae Vitae 14). That covers hormonal pills, condoms, vasectomy and tubal ligation. The Catechism calls such an action “intrinsically evil” (2370), meaning wrong in itself, so that a good intention does not make it lawful (2399).

The reason the Church gives concerns what the act says. Pope John Paul II wrote in 1981 that “the innate language that expresses the total reciprocal self-giving of husband and wife is overlaid, through contraception, by an objectively contradictory language, namely, that of not giving oneself totally to the other” (Familiaris Consortio 32, quoted in Catechism 2370). Paul VI had also warned in 1968 of what would follow if contraception spread: it “could open wide the way for marital infidelity and a general lowering of moral standards,” a man might “forget the reverence due to a woman,” and governments might come to “impose their use on everyone” (Humanae Vitae 17).

Medical treatment is a separate case. When a drug or operation is needed to treat an illness and infertility follows as a side effect, the Church does not object: Humanae Vitae allows “the use of those therapeutic means necessary to cure bodily diseases, even if a foreseeable impediment to procreation should result there from—provided such impediment is not directly intended for any motive whatsoever” (Humanae Vitae 15).

Do other churches allow contraception?

Other churches have answered differently in their own documents. At the Lambeth Conference of 1930 the Anglican bishops, by 193 votes to 67, kept abstinence as “the primary and obvious method” of limiting a family, but agreed that “where there is a morally sound reason for avoiding complete abstinence,” other methods “may be used, provided that this is done in the light of the same Christian principles.” In 1958 the bishops went further, leaving the choice to couples: “the responsibility for deciding upon the number and frequency of children has been laid by God upon the consciences of parents everywhere,” and the planning is to be done “in such ways as are mutually acceptable to husband and wife in Christian conscience” (Resolution 115). The Holy Synod of the Orthodox Church in America taught in 1992 that “married couples may express their love in sexual union without always intending the conception of a child, but only those means of controlling conception within marriage are acceptable which do not harm a fetus already conceived.”

What is natural family planning, and how is it different from contraception?

Natural family planning, or NFP, is the way the Church allows a married couple to space or limit births. The U.S. Conference of Catholic Bishops calls it “the general title for the scientific, natural, and moral methods of family planning that can help married couples either achieve or postpone pregnancy.” The methods rest on observing the signs of the fertile and infertile phases of a woman’s cycle. To postpone a pregnancy, the couple abstain from intercourse and any genital contact during the fertile time. To try for a child, they choose those same days.

The bishops group the methods by the signs a woman learns to read:

The Church holds that NFP differs from contraception in kind, even when a couple’s aim is the same. Paul VI took the objection head on: “In reality, these two cases are completely different. In the former the married couple rightly use a faculty provided them by nature” (Humanae Vitae 16). A couple using NFP to avoid a pregnancy abstain on the fertile days, and when they do make love they change nothing in the act. A couple using contraception have intercourse and act to make it infertile. The Catechism says the natural methods “respect the bodies of the spouses, encourage tenderness between them, and favor the education of an authentic freedom” (2370).

The reason for spacing births has to be a real one. “For just reasons, spouses may wish to space the births of their children. It is their duty to make certain that their desire is not motivated by selfishness but is in conformity with the generosity appropriate to responsible parenthood” (Catechism 2368).

How effective is natural family planning?

It depends on the method and on how closely a couple keep to it. The Centers for Disease Control and Prevention, on a page last reviewed in August 2024 and drawing on the 2023 edition of Contraceptive Technology, gives a typical-use failure rate of 2 to 23 percent for fertility awareness-based methods, and notes that “failure rates vary across these methods.” That group is wider than NFP: the CDC includes couples who use a barrier method on the fertile days, while in NFP, the bishops say, “No artificial methods are used during the fertile time.” On the same page the pill’s typical-use failure rate is 7 percent and the male condom’s 13 percent. Typical use means a method as people actually use it, mistakes included. The bishops’ NFP office says that couples who follow their method’s guidelines “correctly, and all the time, achieve effectiveness rates of 97-99%,” and that couples who are less consistent reach 80 to 90 percent.

Why is sex before marriage a sin for Catholics?

Because the Church holds that sex expresses a total, lifelong gift of self, and only marriage makes that gift. John Paul II wrote: “The total physical self-giving would be a lie if it were not the sign and fruit of a total personal self-giving” (Familiaris Consortio 11). Someone who keeps “the possibility of deciding otherwise in the future,” he went on, “would not be giving totally.”

The Catechism names the sin: “Fornication is carnal union between an unmarried man and an unmarried woman. It is gravely contrary to the dignity of persons and of human sexuality which is naturally ordered to the good of spouses and the generation and education of children” (2353). A couple who live together as husband and wife without marrying, which the Catechism calls a “free union,” come under the same rule: “the sexual act must take place exclusively within marriage. Outside of marriage it always constitutes a grave sin and excludes one from sacramental communion” (2390), that is, from receiving Communion.

Engaged couples are no exception. They “should reserve for marriage the expressions of affection that belong to married love” and “will help each other grow in chastity” (Catechism 2350). Paul’s version is two words, “Flee fornication,” followed by the reason: “your body is the temple of the Holy Ghost which is in you” (1 Corinthians 6:18–19).

What is chastity, and is it only for single people?

Chastity is for married people too. The Catechism defines it as “the successful integration of sexuality within the person and thus the inner unity of man in his bodily and spiritual being” (2337) and asks it of everyone: “All the baptized are called to chastity” (2348). Each state of life keeps it in its own way. “Married people are called to live conjugal chastity; others practice chastity in continence” (2349), which means abstaining from sex. Some give up marriage itself: they “profess virginity or consecrated celibacy which enables them to give themselves to God alone with an undivided heart.”

The Church describes chastity as a kind of freedom. “Chastity includes an apprenticeship in self-mastery which is a training in human freedom. The alternative is clear: either man governs his passions and finds peace, or he lets himself be dominated by them and becomes unhappy” (2339). The Catechism does not expect it to come quickly: “Self-mastery is a long and exacting work. One can never consider it acquired once and for all” (2342).

The Catechism then lists the sins against chastity, beginning with lust: “Lust is disordered desire for or inordinate enjoyment of sexual pleasure. Sexual pleasure is morally disordered when sought for itself, isolated from its procreative and unitive purposes” (2351). Jesus placed that sin in the heart: “whosoever looketh on a woman to lust after her hath committed adultery with her already in his heart” (Matthew 5:28).

Is masturbation a mortal sin for Catholics?

The Church counts it as grave matter, but whether a particular act is a mortal sin depends on how freely and knowingly it was done. The Catechism calls masturbation “an intrinsically and gravely disordered action” because the pleasure is sought outside the union in which “the total meaning of mutual self-giving and human procreation in the context of true love is achieved” (2352). A mortal sin needs all three of the conditions the Catechism names: it “is sin whose object is grave matter and which is also committed with full knowledge and deliberate consent” (1857). On masturbation the Catechism adds that “to form an equitable judgment about the subjects’ moral responsibility and to guide pastoral action, one must take into account the affective immaturity, force of acquired habit, conditions of anxiety, or other psychological or social factors that lessen or even extenuate moral culpability” (2352). The arguments from Scripture are gathered in is masturbation a sin?

Is watching pornography a sin for Catholics?

Yes. The Catechism calls pornography “a grave offense.” It “consists in removing real or simulated sexual acts from the intimacy of the partners, in order to display them deliberately to third parties,” and “it does grave injury to the dignity of its participants (actors, vendors, the public), since each one becomes an object of base pleasure and illicit profit for others” (2354). It also asks governments to “prevent the production and distribution of pornographic materials.”

The general rule on guilt applies here as elsewhere: “the promptings of feelings and passions can also diminish the voluntary and free character of the offense, as can external pressures or pathological disorders” (Catechism 1860). Catholics confess it like any other sin. For the Christian man who wants to stop, Watch the Door is a course of twelve lessons with five minutes of daily practice for ninety days, and its first lesson is free to read.

What does the Catholic Church teach about homosexuality?

The Catechism speaks to the acts, the inclination and the people in turn. Of the acts: “Basing itself on Sacred Scripture, which presents homosexual acts as acts of grave depravity, tradition has always declared that ‘homosexual acts are intrinsically disordered.’ They are contrary to the natural law. They close the sexual act to the gift of life. They do not proceed from a genuine affective and sexual complementarity. Under no circumstances can they be approved” (2357).

Of the inclination and the people who have it: “This inclination, which is objectively disordered, constitutes for most of them a trial. They must be accepted with respect, compassion, and sensitivity. Every sign of unjust discrimination in their regard should be avoided” (2358). “Objectively disordered” describes the inclination, not the person’s guilt. The Vatican’s Congregation for the Doctrine of the Faith wrote in 1986 that “although the particular inclination of the homosexual person is not a sin, it is a more or less strong tendency ordered toward an intrinsic moral evil,” and in the same letter said that “violent malice in speech or in action” against homosexual persons “deserves condemnation from the Church’s pastors wherever it occurs.”

The call is the one given to every unmarried Catholic: “Homosexual persons are called to chastity. By the virtues of self-mastery that teach them inner freedom, at times by the support of disinterested friendship, by prayer and sacramental grace, they can and should gradually and resolutely approach Christian perfection” (2359). Disinterested friendship here means friendship that seeks nothing for itself.

Courage International, which calls itself “an international apostolate of the Catholic Church, which ministers to persons with same-sex attractions,” offers “spiritual support for men and women who experience same-sex attractions and who desire to develop a life of interior chastity in union with Christ.” Its chapter list in October 2026 showed 99 chapters in the United States and more in countries including the Philippines, Brazil and Mexico. A companion group, EnCourage, is for parents and families.

Can a priest bless a same-sex couple?

A short, spontaneous blessing, yes; a rite that resembles a wedding, no. In December 2023 the Vatican’s Dicastery for the Doctrine of the Faith, with Pope Francis’s approval, issued the declaration Fiducia Supplicans, which allows “the possibility of blessing couples in irregular situations and same-sex couples without officially validating their status or changing in any way the Church’s perennial teaching on marriage.” Such a blessing “should never be imparted in concurrence with the ceremonies of a civil union, and not even in connection with them. Nor can it be performed with any clothing, gestures, or words that are proper to a wedding” (Fiducia Supplicans 39).

How many Catholics agree with the Church’s teaching on sex?

In surveys, many American Catholics disagree with parts of it. These figures measure opinion, not behavior. In February 2025 the Pew Research Center asked 1,787 U.S. Catholic adults what the Church should allow. Pew noted that its question about “birth control” did not separate natural methods, which the Church accepts, from contraception, which it does not. About three in ten U.S. Catholics say they attend Mass every week, and Pew found large differences between their answers and those of Catholics who go less often. A 2019 Pew survey of 3,998 U.S. adults, published in 2020, asked whether practices were acceptable “regardless of whether you would do it yourself.”

How many Catholic women use contraception?

Most did in the federal survey data that the Guttmacher Institute analyzed by religion. Its analysis of the National Survey of Family Growth (survey data 2006–08, published 2011) found that among Catholic women at risk of an unintended pregnancy, meaning sexually active, able to conceive and not wanting to, 87 percent used a method other than natural family planning and 2 percent relied on NFP. The same analysis gives the often-quoted 98 percent, which needs its scope: it counts Catholic women aged 15 to 44 who had ever had sex and had used a method other than natural family planning at any point. It is not the share using contraception now.

Where can Catholics get help?

A parish priest can be asked about any of these questions in private, and sexual sins are confessed in the sacrament of penance like any other sin. Catholics with same-sex attraction, and their families, can find a Courage or EnCourage chapter at couragerc.org. A couple who want to learn natural family planning can ask their diocese for a certified teacher. The Church’s full teaching on sex is in the Catechism’s section on the sixth commandment, “You shall not commit adultery,” paragraphs 2331 to 2400.

Related reading

• What the Bible says about sex before marriage
• How to go to confession in the Catholic Church
• How to stop watching porn as a Christian
• Dealing with lust as a single woman
• What the Bible says about sex within marriage
• Is homosexuality a sin? The biblical debate