There was no seed and no conception, unless you subscribe to Mormon interpretation of Luke 1:35 that the "Holy Ghost shall come upon thee" and "the power of the Highest shall overshadow thee," — words Mormons interpret as "carnal relationship."
Mt 1:20 But after he had considered this, an angel of the Lord appeared to him in a dream and said, "Joseph son of David, do not be afraid to take Mary home as your wife, because what is conceived in her is from the Holy Spirit.
Lu 2:21 - On the eighth day, when it was time to circumcise him, he was named Jesus, the name the angel had given him before he had been conceived.
There was a conception.
To say otherwise is to make up your own story because you don't like the way the original was written.
"There was no seed and no conception,"
Who is the woman's seed?
Gen. 3 15, "15 And I will put enmity between thee and the woman, and between thy seed and her seed; it shall bruise thy head, and thou shalt bruise his heel."
Who is going to conceive?
Luke 1:31, "And, behold, thou shalt conceive in thy womb, and bring forth a son, and shalt call his name JESUS."