On this coming Feast of St. Valentine (which is superseded by the First Sunday of Lent this year), World Marriage Day is celebrated. It would praiseworthily make sense to honor true marriages on the feast day of a Roman priest and martyr for defending the Sacrament of Holy Matrimony. But unfortunately, nobody in the secular world (and many in the clergy) have no clue what marriage is all about.
College campuses nowadays promote sexual perversion every day of the year, and during the month of February invoke Valentine with their perversions. Yale Sex Week is the most vulgar.
The bottom line is, if these kids are not married, they have no business taking part in intercourse. It's that simple. But condoms are available for free on most Novus Ordo "Catholic" college campuses. As long as contraceptives are made available, college students will have sex with one another.
On the other hand, married couples who refuse to perform intercourse without a serious reason commit a mortal sin. They are the only ones who have the right to procreate.
Obviously love of each other is very important in order to discern marriage, but the procreation of children on God's terms is the first aim of marriage. Love and mutual assistance are only centimeters behind.