One of the arguments that I have heard against the virgin birth is that it is impossible for a complex being to be born without the genetic material from both the male and female. Science is demonstrating that it is indeed possible. For the second time in recent years it has been demonstrated that a female shark has given birth without the involvement of a male. You can read about it here. This does not prove that Jesus was virgin born but it does suggest that it is more scientifically reasonable than previously thought.