Estimates suggest that, on average, Americans behave as if they value a year of their life at, more or less, $100,000. This would put an average American life at a “revealed preferred” value of somewhere around $7 million. That might be high– depending on one’s methodology one might get numbers closer to $2 million. But surely the vast majority of people value their entire lifetime as worth more than one million dollars. They would not, for example, be willing to die in exchange for a million dollars. And they would be willing to pay (in medical care or what have you) $20,000/year to stay alive. So there is a starting point for thinking about the cost of a life.
One way to think about abortion (not the first way, or the last way or the only way, but one way) is as a bargaining failure. Hypothetically(!) imagine the fetus as an agent wishing to make a deal with the mother. If he could, the fetus would, judging from the above, happily contract with the mother to pay her if she would carry him to term, and let him be adopted by some yuppie family or, noticeably worse, put in foster care. (There are about 120,000 adoptions a year in the U.S., and my vague impression is that demand outstrips supply). It is not unreasonable, in fact, that he would be willing to make annual payments to the mother of, say $20,000/year. The payments could be made out of an account that could start out in the red but the child would make up for it later on with higher payments in adulthood.
Perhaps some children would rather die as a fetus than deal with a lifetime of such high payments, in which case, the question becomes what is the minimum payment the child must make in order to get the mother to bear the extra 5-8 months of pregnancy with all its incumbent problems?
Would most women, once they are already pregnant, be willing to carry a child to term for a million dollars? Or $7 million? Or even $100,000? Some would and some would not. That hypothetical market doesn’t exist and quite possibly never could, for a whole host of reasons, but even in its absence thinking about it points out the staggering asymmetry between the benefit to the fetus and the cost to the mother. What a tremendous opportunity for gains from trade that will never be realized!
And, of course, these are just averages. Since we are thinking about a group of over a million mothers and fetuses, surely the averages apply to enough people to make the thought experiment worth thinking about.