Is the afterlife mostly populated by the souls of embryos?

Just about every branch of Christianity teaches the human soul becomes implanted in the embryo somewhere before birth. Many branches also believe the human soul is immortal. At the same time, I've read reports that as many as 60% of pregnancies end in miscarriage . This is in the context of our very developed medical system, historically speaking, so stands to reason the miscarriage rate was even higher in the past. Altogether, does this imply that most of the immortal souls in the afterlife are the souls of embryos, at least according to the views of most Christians?