Or zygote. So... is your keyword for this issue 'unwanted?'
Aren't all abortions-on-demand the 'unwanted' of babies-by-any-other-name?
Is unwantedness the key issue for you?
Absolutely, and the key to it is the requirement for the mother's body and the mother's absolute sovereignty over that body. There's nothing viable about the embryo whatsoever w/o the mother's body being involved, until some later stage of the pregnancy — later stage being the keyword. For the purposes of this discussion, contraception is essentially what's involved here.