The Anchoress defends the church teaching that "every sperm is sacred." After explaining how "control is often an illusion" because birth control doesn't always work and "God will do what He will, sometimes, whether you’re open to it or not, in hopes that you WILL become open, and more open, to his loving gifts" she hits upon one of the Church's core contradictions:
The church understands and respects nature sooner or later fertility ends, that does not mean sex ends. One of the common misunderstandings is that “the church says sex must always and only be about procreation, and if it’s not possible, then sex is a sin.” This is nonsense. Sex is the gift and privilege of married couples, both pleasurable and procreative. When fertility has come to an end, when the possibility of new life is no longer there, that means the procreation part has ended, not the pleasure.
I don't dismiss this at all. But if sex can be merely pleasure and not procreation because of the restraints of our nature, what about the gays? The issue is explored at length in Virtually Normal.