Proposition 8 declared unconstitutional

[Philippus Flavius Homovallumus]

And what about couples who choose not to have children? Should they be allowed to marry?

They might choose differently later, and allowing them to marry seems to encourage that.

Edit: Or women who have had hysterectomies? No chance for kids there.

Physical disability might be a mitigation, but I'm inclined to say "no" actually.

Of course, none of this prevents you from getting a Civil Partnership.