That would require research. I thought the same thing. Maybe labor caused the blood pressure to jump more and that is how they diagnosed it.
this lady was saying.......can't remember, it was a few days after the birth, not a week though. Didn't feel good and while trying to call the hospital, had a blinding headache and doesn't remember much after that. Thankfully, about the same time her husband walked in, home early from work because she had texted about not feeling great and they got her to the hospital. She had had other issues at the birth so she was in for like 3-4 days but then this happened like 1-2 days after that.