No, Mr. Jesse Nix, marriage is not a right granted by the state. States do not have rights. Only individual people have rights. Governments are the collective necessity to keep us from violating each other's rights.
The yet-to-be-conceived generation has those same rights as surely as we do. We have no more right to sexually endanger or compromise their right to life than we do each other's.
Bottom line, no one has any unalienable right to sexual involvement with anyone else. Any right can only be collectively granted. A marriage license works on the same collective principle as a driver's license.