Is IVF a Sin?

On an internet discussion board, several (Christian and non-Christian) have been interacting on the question of whether IVF is, according to Christianity, a sin. Without going into tremendous detail here, IVF (In Vitro Fertilization) is an artificial reproductive technology (ART) used to fertilize a woman's egg outside of her body and implant it into her uterus later. The process may move as quickly as having one egg fertilized and immediately implanted, or the process may be longer where several eggs are fertilized and 2-3 are implanted and several embryos stored for use another time. And then there are variations in between as well as some extreme circumstances like the so-called Octomom story of 1009. Some couples choose to have the embryos screened for genetic defects or gender, never implanting the "bad" ones. Others will freeze and store dozens of eggs, not knowing exactly what will become of them in the future. Some of the debate over embryonic stem cell research stems from the existence of hundreds of thousands of embryos that are currently in storage, many of which will never be claimed by their parents. Yes, I said parents.

So below is the discussion which caught my attention:
I don't know that IVF is a sin. I have issues with it, but they are only my opinion, and I have no Biblical reference for it or any other reference. Some of my issues include fertilization of numerous embryos: what do they do with the ones they don't implant? If they implant several embryos, what happens if they all implant? I know several people who were offered selective abortion, which I believe is wrong. And when it comes to choosing gender, I just think that is way wrong.
However, I would not presume to judge you for undergoing IVF. It is ultimately your choice. If you have prayed about it and strongly feel it is the right thing to do, then go for it. 

It's a good thing we don't make all of our decisions according to the few final words in this emotional recommendation. She believes there is something wrong with the use of IVF if it involves the creation of unused embryos, the destruction of embryos, or sex-selection. Her concern is rooted in the concept of human dignity, that life is precious and worthy of respect at every stage. Sadly, she does not explain that the embryo is a human at its earliest stage and destroying a tiny human person is to kill that person. If we think something is wrong, we ought to be able to say why, but perhaps she was driven by the higher moral principle to not judge. That one she claims without hesitation and it appears to be at the top of her moral hierarchy. Is this the kind of advice we should be giving for any questionable situation? "Pray about it and if it feels right...." ? Perhaps "continue to seek wisdom and knowledge from others AND continue to pray" is the better course.

So the question is, is IVF a sin? Let's rephrase it. Is killing another person a sin? If the technology involves the destruction of human embryos, we are in safe, though sad, territory identifying the act with an act of sin.