Here is the earliest born baby at 21 weeks: https://www.usatoday.com/story/news/nation-now/2017/11/14/mom-delivers-earliest-premature-baby-ever-and-chooses-resuscitate-miracle-aughter-now-healthy-toddle/861386001/
Now Roe v Wade legalized abortion until 24 weeks, people on the left say that baby at that point is just "a clump of cells" that has "no cognitive capacity", it "cannot feel anything". Look at the picture and now tell me where you would put the limit. The baby at that point (21 weeks) can obviously cry, feel, see, hear etc.
Moreover, "the clump of cell" transplants are now possible at any point in pregnancy, there have been a few cases where the mom got killed in a car accident and the baby was transplanted and subsequently grew. Fetal transplants were first successful in 1922, more than a century ago.
So the case for abortion is really, really, slim, if you're going into surgery anyway, why not have the baby transplanted to a willing mother. Yes, if the mom is in danger, this has always been and remains legal, but that's literally a fraction of the pregnancies.