Jay is correct that the term fetus by itself is a medically correct description of a biological stage of development that we all have passed through. There is nothing objectionable about this term, and our shyness about using it can be construed as a hesitancy to acknowledge biological facts.
However, it is quite sad that the other side of this debate is using this accurate term in an intentional effort to deceive. The point of using technical language is to clarify and to be as specific as possible. "Jaw Surgery" is not nearly as descriptive or accurate as "2-Piece Maxillary Lefort I advancement osteotomy". The latter term is used when boarding the case or dictating the report, but in almost every other context, I would say upper jaw surgery.
The term fetus is used by pro-abortion choicers to attempt to differentiate human beings that they find valuable and those they don't. They are not attempting to describe the stage of development of a human being, but instead deceive by using a technical term. This is unfortunate. There is nothing wrong with using the term nulligravida to accurately describe a woman who has never been pregnant - but using the term to denigrate their value as a human being would not be accepted.
My solution is pretty simple. I try not to use the term fetus alone. I will always describe a human fetus, or better yet, a fetal human being. Adding the term human is not a rhetorical technique, but a clarification. It fits in well with the goal of using technical terms in the first place - better accuracy. This is done all of the time. My sister once came home from school stating that she had dissected a fetal pig - not a 'fetus'. (Although they probably don't do such things any longer).
Lastly, I have to admit that I changed the name of Jay's post slightly in order to say - More Cowbell!