Nobody has argued against Mary's virginity before and during her pregnancy. The disagreement is whether she remained a virgin after giving birth to Jesus.
Also, the stone rolled away from the tomb. One of "the three Marys" saw the open tomb, saw the body was gone, saw Jesus, thought he was a gardener, and asked for Jesus' body.
And the God Who can leave a closed tomb or enter a closed room would have no trouble leaving Mary’s womb eschewing the usual deliver method.. One of the Gospels relates the tomb story as the Angel rolled away the stone for the approaching women who were discussing how they would get into the tomb because of the large sealing stone. Jesus was already ‘out’ of there. But thank you for the BTTT.