To be clear, my background is in biology. I’m not an obstetrician. The “other symptoms” to which I was referring related to a failure of implantation rather than the detection of a successful one may be the inverse of your question and I was specifically referring to the discharge.

My understanding is that, especially with the development of IVF technologies, they’ve introduced additional testing methodologies, but I’d defer to someone with more experience in that field.

If you want to talk about how eyes evolved a couple of dozen times or why UFOs are almost definitely not aliens though, I’m your guy.