One of the problems we have with regard to the embryo is that it isn't seen. Instead of embryo we should speak of a child who is in the initial phase of development. Because we cannot see him, he is in a situation of tremendous danger, at tremendous risk.
The words we use are indeed extremely important. Further on in this post I'll record a few thoughts on the word "child"; but before doing so I'd like to refer to the general use of the term "unborn".
While it is of course a statement of fact, I have always felt there was a certain insufficiency in the word. My slight discomfort arises from a phrase which occasionally used to crop up in the loftier kind of political speech, when the politician wanted to inspire his listeners with a vision of the faraway sunlit uplands to which his party’s policies would undoubtedly lead the nation. He would refer to “generations as yet unborn”.
In that example the generations did not in fact exist at the time of the speech. Might the term “unborn” convey something of that same sense of non-existence - or of not yet existing - when used in reference to the child in the womb? Not to us, of course; but does its use miss an opportunity to impress upon a wider and less informed audience the reality, the totality, the existence here and now, of an actual human being, from the instant of his or her conception?
Returning to the word "child", I’d love to hear it used, as Mgr Carrasco recommends; and used as the standard term. “Baby” would be good too; but I feel that the use of “child” emphasises even more strongly the individuality, the humanity, the personhood, the sense of continuity with all stages of a person's development and growth to adulthood. So for me, it is “the embryonic child”, “the gestating child” or "the child in the womb" which fits the bill better than any other phrase.