Pope John Paul II, in his most definitive pronouncement on family issues, unequivocally rejected yesterday any easing of the Catholic Church's ban on artificial birth control, sex outside marriage and divorce.

The statement appears to condemn the unofficial but widespread American practice of permitting divorced Catholics who have remarried to receive holy communion -- a violation of church law -- if they can do so in good conscience.

The 175-page document condemns governments that promote birth control programs to curb population, saying they are guilty of a "grave offense against human dignity and justice." It also presents the strongest plea for equal rights for women yet enunciated by the pope, but at the same time emphasizes the importance of women's "maternal and family roles."

The document, released in Rome, is the pontiff's response to the 43 recommendations on family life developed by a month-long worldwide Synod of Bishops held in Rome in the fall of 1980. Addressed to bishops, priests "and to the faithful of the whole Catholic Church," which reports a global membership of 700 million, it is considered the official teaching of the church on family issues.

Its impact is difficult to predict, since repeated studies have shown that vast numbers of Catholics no longer follow their church's teachings on many matters of sexual morality.

During last year's synod, Archbishop John Quinn of San Francisco told his fellow bishops that 3 out of 4 American Catholic women use artificial birth control methods despite the church's teaching against it and that only 29 percent of U.S. Catholic priests believe contraception is wrong and deny absolution to those who use it. Quinn called for a reexamination of the church's position on birth control.

The Rev. Richard McBrien of Notre Dame University, one of the church's leading theologians in this country, citing similar figures in a telephone interview yesterday, said, "I don't suspect it is going to change anybody's mind, one way or the other." Catholics today, he said, "have learned what it means to be selectively obedient" to church teachings.

In reiterating the church's traditional position that marriage is indissoluble, Pope John Paul stated that divorced persons who have remarried "are unable to be admitted" to holy communion because "their state and condition of life objectively contradict that union of love between Christ and the church which is signified and effected by the eucharist," and because admitting such persons to communion would cause the faithful to be "led into error and confusion" regarding church teaching about marriage.

Only if divorced and remarried persons repented and proceeded to "live in complete continence, that is, by abstinence from the acts proper to married couples," might they be readmitted to the eucharist, the pope said.

The ruling seems to strike at what has been called the "good conscience solution," which has unofficially readmitted to the sacrament hundreds of thousands of American Catholics who have divorced and remarried. In that procedure, which has no standing in canon law, couples examine the reasons for their divorce and second marriage in consultation with a sympathetic priest, and decide on their own whether they can with a clear conscience resume receiving communion, which Catholics believe is central to their eternal salvation.

Concerning the role of women, the pope said that God, in creating the human race, "gives man and woman an equal personal dignity." He pointed out that Jesus, on Easter morning, "entrusted to women to carry the good news of the resurrection . . . ," the heart of Christian belief.

On the one hand, the pontiff rejected cultural traditions that limit women's role "to be exclusively that of wife and mother, without adequate access to public functions which have generally been reserved for men." But he also said that "the mentality which honors women more for their work outside the home than for their work within the family must be overcome."

Among other issues touched in yesterday's statement, the pontiff:

* Advised fathers to assume their share of the responsibility in raising their families.

* Totally rejected trial marriages, "unions without any publicly recognized institutional bond" and any sex outside marriage.

* Warned parents to monitor their children's television viewing and tastes in reading material "to protect the young from the forms of aggression they are subjected to by the mass media."

* Promised a "Charter of Family Rights" to be prepared by the Vatican, spelling out such issues as the right to bring up children within family religious and cultural traditions, the right of families to emigrate in search of a better life and "the right, especially of the poor and the sick, to obtain physical, social, political and economic security." The charter is "to be presented to the quarters and authorities concerned," he said.