Robert, if you think that no one finds early miscarriages regrettable or tries to do everything possible to prevent them then you haven’t known anyone who has gone through one, or who has had a high-risk pregnancy. A great deal of medical research (much of it funded by the NIH these days) has also gone into better understanding the causes of early miscarriages and finding ways to prevent them. Almost all early embryo deaths happen before the mother even knows she’s pregnant, so it wouldn’t really be possible to do much to prevent them, but those that occur later are very often found deeply regrettable by the families involved, to put it mildly, and a huge amount of effort and money are spent (by individuals and by our society as a whole) trying to prevent them.
Even if we were so callous as to treat such deaths as meaningless, it’s hard to see how that would justify intentional killing unless your right to life were really just a function of other people caring about you. Let’s hope, for the sake of those most vulnerable and most alone in our world, that enough of us can see that there is more than that underlying our most basic obligations to one another, and can pass laws that embody that understanding and that protect the lives of those whose families may not want them no less strenuously than those of others more fortunate.