There have been abortifacient drugs for the whole of recorded history. Chemical contraceptives, too, some apparently very effective. It’s an interesting topic.
Something that's not always made clear up front on this issue is that modern birth control pills don't always prevent fertilization. Sometimes they allow an egg to be fertilized, but then prevent implantation. In these cases it effectively acts as an abortificant. The objective is not just to prevent surgical abortions, or "morning after" pills like RU486. If the standard is that anything that results in killing a fertilized egg then even regular birth control pills will be illegal.