I would say that both have equal value, to the point where intentionally choosing to kill one is an unacceptable choice. And I would also say that the triage comparison doesn't hold up, because in this case, the fetus is actually the healthier party of the two. Unfortunately, we don't yet have the ability to create an "artificial womb" that could easily resolve the issue without any moral qualms, though I hope that can come to pass in the near future.
But seriously, I don't want to be doing this. I'm sure you don't want to be doing this. We know it's going to go nowhere. The only reason I made the first comment is because Little Miss Trollio broached the subject in the first place. So why should we indulge her?