Jesus answered, "Truly, truly, I say to you, unless one is born of water and the Spirit, he cannot enter the kingdom of God.
This is talking about baptism, not natural birth. Where are you getting that mistaken idea?
Joh 3:5 Jesus answered, Verily, verily, I say unto thee, Except a man be born of water and of the Spirit, he cannot enter into the kingdom of God.
Joh 3:6 That which is born of the flesh is flesh; and that which is born of the Spirit is spirit.