Actually. Both the sperm cell and the egg cell are biologically not alive, because they cannot proliferate by themselves (They have metabolism, especially the sperm cell, which is using it to propel itself). Only the fertilized egg cell can do that. Therefore scientifically life begins at conception.
It's actually funny to see, that the European countries have no problem accepting this definition, even though they in general do allow abortions. Yet in order to do so some of them had to go through some legal struggles to legalize abortion even though it actually kills a person, while others simply ignored that contradiction.