I hope you don't eat meat.
I guess for me it never comes back to "life" as in when the egg and sperm meet and a genetically distinct organism is created. Yes, that is life, but I have no more responsibility to it than the steak I ate for dinner last night (and arguably, the mashed potatoes). For me it comes back to the ideas of sapience and sentience, neither of which a foetus has (before a certain age) and both of which my steak had (depending on your definitions of the terms).
A foetus is not self-conscious, has no self-awareness, is not sentient and is certainly not sapient. The fact that it has the potential to be doesn't come into it for me - how do I know that the steak I ate (or more appropriately to the context, the veal schnitzel I had a couple of days ago) didn't have the potential to be the first self-aware, self-conscious, sapient and sentient cow? I didn't, but that doesn't really matter because I don't have any romantic notions regarding potentiality or the sacredity of life.