I think the issue of cloning has made people think that reproduction is something that individuals do on their own, as opposed to something marriages do, a man and woman together. Also, using the term "fully human" about individuals plays into this, as though people do not need a complimentary person of the other sex to fully represent the species, and fully flower their own body's potential. I know that in this narcissistic "me" society, the idea that we should have to cooperate with someone to reproduce and share our children must be frustrating, but to take it to Randolfe Wicker's conclusion is just misanthropic.
Is there a right to procreate?
More and more people these days seem to think that procreation is a right of an individual, and completely independent of marriage, but there is lots of legal history that reminds us there has never been a right for an individual to procreate, but only a right to choose another person to marry with whom you may then mutually attempt to procreate. As Ampersand points out on Alas, A Blog: "ability to bear children was not a traditional ground for fault-based divorce." This means that if one of the partners is thought to be infertile after the marriage, the state would not allow the other partner to look for someone else with whom they might procreate. So clearly, the state didn't feel that anyone has been denied any civil right to procreate by being forced to remain married to a sterile person, or it would allow them to divorce and try it with someone else. (of course, now no-fault divorce is possible, but not because of a new found procreation right.) There is only a right to not be sterilized, and there is a right to marry someone and then attempt to procreate (aka, have sex). But there's no "right to procreate." Marriage is a license to attempt to procreate. If we don't want two people to attempt to procreate, we withhold the license. We withhold it from siblings due to health risks and we can withhold it from couples of the same-sex for the same reason.