A bunch of cells in rapid development with the potential to become a human being. Murder is a strong term, but in a broad sense I don't think your insinuation is wrong per se.

This might be getting a bit controversial, but for the sake of discussion:

The important thing here is, do you mind if that potential for life is taken away. In this case we place priority on the human being that eventually has to dedicate her life to that potential. Or is that new potential more important than that already existing, conscious human being (especially when there are physical / mental problems involved)?

It comes down to why we live, and why must we live? Personally I believe trying to avoid (potential of) suffering is a more reasonable concept.

If one gives life to a baby, you give it a potential for suffering which it otherwise does not. I'd say the ways one can suffer is of a greater weight than the ways one can be happy. So if you go the route of creating life, you better be damn confident that you are in a good position to do that.

In that philosophy 'murdering' a potential with a large chance of creating more suffering for the collective is not that bad. One might view this differently when the being is conscious and might actively not want to die, as we bring the complexity of individual human choice to the table and what worth that has; but I think we can agree that is not applicable on the unborn potential human being discussed in this topic.