Who can receive the sacrament of Holy Orders?
A baptized, Catholic man who is called by the Church to be a deacon, priest, or bishop can be validly ordained to that ministry.
Is it demeaning to women that only men may receive the sacrament of Holy Orders?
The rule that only men may receive Holy Orders in no way demeans women. In God's sight, man and woman have the same dignity, but they have different duties and charisms. The Church sees herself as bound by the fact that Jesus chose men exclusively to be present at the Last Supper for the institution of the priesthood. Pope John Paul II declared in 1994 "that the Church has no authority whatsoever to confer priestly ordination on women and that this judgment is to be definitively held by all the Church's faithful". Like no one else in antiquity, Jesus provocatively affirmed the value of women, bestowed his friendship on them, and protected them. Women were among his followers, and Jesus highly valued their faith. Moreover, the first witness to the Resurrection was a woman. That is why Mary Magdalene is called "the apostle of the apostles". Nevertheless, the ordained priesthood (and consequently pastoral ministry) has always been conferred on men. In male priests the Christian community was supposed to see a representation of Jesus Christ. Being a priest is a special service that also makes demands on a man in his gender-specific role as male and father. It is, however, not some form of masculine superiority over women. As we see in Mary, women play a role in the Church that is no less central than the masculine role, but it is feminine. Eve became the mother of all the living (Gen 3:20). As "mothers of all the living", women have special gifts and abilities. Without their sort of teaching, preaching, charity, spirituality, and guidance, the Church would be "paralyzed on one side". Whenever men in the Church use their priestly ministry as an instrument of power or do not allow opportunities to women, they offend against charity and the Holy Spirit of Jesus. (YOUCAT questions 256 & 257)
Dig Deeper: CCC section (1577-1578) and other references here.
Part 2: The Celebration of the Christian Mystery (1066 - 1690)
Section 2: The Seven Sacraments of the Church (1210 - 1690)
Chapter 3: The Sacraments at the Service of Communion (1533 - 1666)
Article 6: The Sacrament of Holy Orders (1536 - 1600)
VI. WHO CAN RECEIVE THIS SACRAMENT? ⇡
"Only a baptized man (vir) validly receives sacred ordination."66 The Lord Jesus chose men (viri) to form the college of the twelve apostles, and the apostles did the same when they chose collaborators to succeed them in their ministry.67 The college of bishops, with whom the priests are united in the priesthood, makes the college of the twelve an ever-present and ever-active reality until Christ's return. The Church recognizes herself to be bound by this choice made by the Lord himself. For this reason the ordination of women is not possible.68
66.
CIC, can. 1024.
67.
Cf. Mk 3:14-19; Lk 6:12-16; 1 Tim 3:1-13; 2 Tim 1:6; Titus 1:5-9; St. Clement of Rome, Ad Cor. 42,4; 44,3:PG 1,292-293; 300.
68.
Cf. John Paul II, MD 26-27; CDF, declaration, Inter insigniores: AAS 69 (1977) 98-116.
No one has a right to receive the sacrament of Holy Orders. Indeed no one claims this office for himself; he is called to it by God.69 Anyone who thinks he recognizes the signs of God's call to the ordained ministry must humbly submit his desire to the authority of the Church, who has the responsibility and right to call someone to receive orders. Like every grace this sacrament can be received only as an unmerited gift.
69.
Cf. Heb 5:4.