Setting aside poor phrasing that seems to run counter to what Dek is saying, Dek’s point makes plenty sense when understood that he is speaking about the moral value of a life.
To illustrate, miscarriage is common in pregnancy and usually occurs fairly early on. Losing a child at 6 weeks is painful. I think losing at several months would feel worse. I don’t know that either of those compares to losing a child at 14 years old. That’s not to say that each life has a different moral weight, but the sense of loss seems greater for different situations. In the “[fill in the blank] Just Died!” thread there was discussion of it being basically ‘worse’ when a young person dies. I think that’s the thinking that caused Dek to fall into that poor phrasing while trying to talk about moral value of life. He tried to recognize the reality of those feelings while trying to stick to his point.
As for the use of the word “murder,” I admit that doesn’t always sit well with me, but there are laws that treat the killing of a fetus or embryo as murder (as when someone assaults a pregnant woman).