Humani Generis states Catholics are to believe monogenism.
From Arcanum by Pope Leo XIII:
“We record what is to all known, and cannot be doubted by any, that God, on the sixth day of creation, having made man from the slime of the earth, and having breathed into his face the breath of life, gave him a companion, whom He miraculously took from the side of Adam when he was locked in sleep.”
"The Catechism of the Catholic Church
"# 375 The Church, interpreting the symbolism of biblical language in an authentic way, in the light of the New Testament and Tradition, teaches that our first parents, Adam and Eve, were constituted in an original “state of holiness and justice”. This grace of original holiness was “to share in. . . divine life”.
“# 390 The account of the fall in Genesis 3 uses figurative language, but affirms a primeval event, a deed that took place at the beginning of the history of man. Revelation gives us the certainty of faith that the whole of human history is marked by the original fault freely committed by our first parents.”
Peace,
Ed
I confess … that all men from Adam onward who have been born and have died up to the end of the world will then rise again and stand “before the judgment-seat of Christ,” together with Adam himself and his wife,
who were not born of other parents, but were created: one from the earth
and the other from the side of the man (… ). Pope Pelagius I
[We confess] … that after [Jesus’] spirit was already rendered up, his side suffered perforation by a lance, so that through the ensuing flow of water and blood, the one and only, immaculate, virgin holy Mother Church, the Spouse of Christ, might be formed,
just as from the side of the first man, cast into sleep, Eve was formed for him unto marriage. This happened so that the reality manifested in our last Adam, that is, Christ, might correspond to a certain prefiguring of that reality constituted by the first and ancient Adam, who, according to the Apostle, “is a type of the one who was to come” [cf. Rom. 5: 14] Ecumenical Council of Vienne in 1312
EVE, the first woman, made out of a rib of Adam (Gen. ii. 21); induced by the serpent to eat the forbidden fruit (iii. 6); persuades Adam to eat thereof (6); her sentence (16); God makes her a garment of skins (21); mother of Cain (iv. 1); of Abel (2); of Seth (25) and of daughters (v. 4)
Of all books ever written, this fivefold book of Moses is the only one that enlightens us
with infallible certainty on the origin of all things in this universe, visible and invisible;
on the creation of mankind and their destinies; on their duties, during this life, toward their Almighty Creator and toward each other, and on the rewards and punishments of the eternal life hereafter… . Before the coming of Christ the whole pagan world was plunged in darkness impenetrable concerning the origin of man and the world, and the sublime destinies appointed in Christ for Adam and his posterity in the very beginning.
Christian teaching dispelled this midnight darkness and revealed to all believers both the secret of man’s origin and the incomprehensible glory of his supernatural destinies… . So, in these first verses and pages of Genesis — the Book of Origins — we are treading on abysses of revealed truth — of truth which explains to us both the world beneath and around us, and that unmeasured world which extends on all sides above and beyond our little globe, … Bible dictionary by Fr. B. O’Reilly, first published in the 1850s or early 1860’s approved by 23 Bishops
This, our Holy Mother the Church believes and teaches: When God was about to make man according to his image and likeness in order that he might rule over the whole earth, He breathed into the body formed from the slime of the earth the breath of life, that is, a soul produced from nothing… . And blessing the first man and Eve his wife
who was formed by divine power from his side, God said: “Increase and multiply, and fill the earth” (Gen. 1: 28) draft schema prepared by bishops and theologians of Vatican Council I
What is the true origin of marriage? That, Venerable Brethren, is a matter of common knowledge. For although the revilers of the Christian faith shrink from acknowledging the Church’s permanent doctrine on this matter, and persist in their long-standing efforts to erase the history of all nations and all ages, they have nonetheless been unable to extinguish, or even to weaken, the strength and light of the truth. We call to mind facts well-known to all and doubtful to no-one: after He formed man from the slime of the earth on the sixth day of creation, and breathed into his face the breath of life,
God willed to give him a female companion, whom He drew forth wondrously from the man’s side as he slept. In bringing this about, God, in his supreme Providence, willed that this spousal couple should be the natural origin of all men: in other words, that from this pair the human race should be propagated and preserved in every age by a succession of procreative acts which would never be interrupted. And so that this union of man and woman might correspond more aptly to the most wise counsels of God, it has manifested from that time onward, deeply impressed or engraved, as it were, within itself, two preeminent and most noble properties: unity and perpetuity. Pope Leo to the world’s Catholic bishops
.