God displayed no sexual intercourse to Mary because He is God, which means that He is omnipotent, omniscient, & omnipresent. This conveys that He does not need a cock of the man neither the seeds of men to input a woman's womb for the purpose of childbirth.
The context of Scripture never said any need for sex, neither it was explained. Therefore it is a miracle because that is who He is without the need of procedure, stability, & time.
Miracles defies the laws of science in which we know & experience reality, & such examples are the 10 plagues of Egypt, the diverse tongues in the event of the Tower of Babel, the parting of the Red Sea, the sun stood still, the victory of Israelites against super nations including the giants, the enormous strength & skin of Samson, the brass staff of Moses that turns into staff to snake & vice versa which also healed those who are sick, God talking to Baalam through a donkey, Jesus standing on water, the feeding of the 5,000, the resurrection of the dead, & so on. Of course the LORD also did the miracles first to Sarah whom she gave birth to Israel & secondly to Elisabeth whom she gave birth to John the Baptist. This means the third time is Jesus Himself.
The LORD never really explains these miracles because it beyond science & understanding. That is why in the holy Scriptures, God wants us to fully trust in Him 😁
Genesis 18:1-15
Genesis 21:1-7
Genesis 21:1-7
Romans 4:16-22
Luke 1:1-80
Genesis 18:14 KJV
Is any thing too hard for the LORD? At the time appointed I will return unto thee, according to the time of life, and Sarah shall have a son.
Luke 1:36-38 KJV
And, behold, thy cousin Elisabeth, she hath also conceived a son in her old age: and this is the sixth month with her, who was called barren. [37] For with God nothing shall be impossible. [38] And Mary said, Behold the handmaid of the Lord; be it unto me according to thy word. And the angel departed from her.
Proverbs 3:5-6 KJV
Trust in the LORD with all thine heart; and lean not unto thine own understanding. [6] In all thy ways acknowledge him, and he shall direct thy paths.