[jas3]

Being destroyed in a petri dish or being *allowed* to die there, is NOT dying *naturally*. Dying natuarally is not murder. Deliberately ending a life is. When a fertilized egg fails to implant, it's not the choice of the woman and likely she doesn't even know that it happened; that is not murder.

I agree that destroying a cell is not morally equivalent to letting it live. But I don't see why not implanting a cell and letting it live it's full life is morally equivalent to deliberately ending a life. The cell will have lived it's full life. It will have been born, aged, and have died. How is that deliberately ending a life? If the blastosphere is alive, and dies of old age, how is that different from any other cell dying of old age?

jas3

[metmom]

When this in vitro fertilization occurs, the parents do it with the knowledge that they are going to choose to let one live and the rest die, whether by direct action or through inaction, same difference.

[syriacus]

How is that deliberately ending a life?

A life would be ended through neglect. I guess you could label it a wrongful death.