"Obliterate proof of the miracle"???
Exactly what kind of *proof* of the miracle of the virgin birth would her having sex with her husband obliterate that giving birth would not?
You know there's really only one way to determine virginity? I can't believe that you are implying that that occurred to *prove* the miracle.
The only requirement for the prophecy is that a virgin conceive and bear a son. What happens or happened after that is irrelevant.
“And she said to her: Salome, Salome, I have a strange sight to relate to thee: a virgin has brought forth — a thing which her nature admits not of. Then said Salome: As the Lord my God liveth, unless I thrust in my finger, and search the parts, I will not believe that a virgin has brought forth.
20. And the midwife went in, and said to Mary: Show thyself; for no small controversy has arisen about thee. And Salome put in her finger, and cried out, and said: Woe is me for mine iniquity and mine unbelief, because I have tempted the living God; and, behold, my hand is dropping off as if burned with fire.”
www.earlychristianwritings.com/.../infancyjames-roberts.html
Yes, most probably she did get examined by a physician who ascertained her virginity even in her old age. Why is this so astonishing? Have you ever been to see a doctor?