General Discussion
In reply to the discussion: Well look what the Mayo Clinic just told me about abortion. Please spread this very well concealed [View all]Igel
(37,473 posts)The MAP prevents implantation. You can take it in week 1 and 2, but those have pretty much nothing to do with actual pregnancy. They're counting weeks in which pregnancy doesn't happen--before ovulation. Why count them? Because women have a decent idea as to when they're menstruating without thinking about it too hard, but knowing when they're ovulating is a bit trickier.
So you count from what's easily knowable, now from what you almost certainly don't know. Even if you're counting a couple of weeks before ovulation and copulation and calling that "gestation."
You take the MAP presumably when you suspect you'll be fertile, immediately after insemination. That would be "week 3" as far as the Mayo Clinic counting is concerned. Implantation follows a few days later. I suspect a lot of women would take it "just in case," even if there's not much of a case to be "just in." Then again, I knew a 17-year-old girl convinced that men provided the egg and women made sperm. It was clear why she'd failed the biology portion of her standardized high-school science test.
A standard birth control pill prevents ovulation. As a consequence, there's nothing to be fertilized.
It's back to whether a fertilized lump of cells counts as a "baby" or person or not. Along the way, there are fairly clear milestones that may or may not be important for some people. "Implantation" is one of them--by itself, that single step isn't a truly huge difference for the fertilized egg and the stages that follow (but it allows more important changes to happen).
For others, what's important is the manner that oxygen gets to the fetus' bloodstream. Again, the fetus doesn't really change much going from one oxygen-delivery system to the other.