Yes. That such marital relations would not, in a time when birth control would have been unknown, result in other children being conceived?
I'm not sure I understand the question. If they had had relations, they surely would have had other children. Since they did not have relations, they did not have other children.
To me the notion is ludicrous to say the least. What would be the purpose of such a belief?
The affirmation of the Truth.
What would have been the purpose of such a marriage?
To provide for the care, upbringing, and instruction of the Most Precious Child on earth.
Is it entirely ludicrous to think that a man and woman who were informed by God that they would be responsible for the Savior of the World might be a bit, um, focused on the task at hand?
SD