Sex, he said, is “supposed to be for purposes that are yes, conjugal and unitive, but also procreative.”
They're supposed to be within marriage, for purposes that are, yes, conjugal... but also procreative.
Julian Suvalescu, professor of practical ethics at Oxford, has advocated a position he calls “procreative beneficence.”
procreative pro·cre·a·tive (prō'krē-ā'tĭv)
Capable of reproducing; generative.
Of or directed to procreation.
procreate pro·cre·ate (prō'krē-āt')
v. pro·cre·at·ed, pro·cre·at·ing, pro·cre·ates
To beget and conceive offspring; to reproduce.
To produce or create; originate.