You want abortion banned because it kills an innocent human being. How many zygotes do you believe is equal to the life of a woman? If the answer is 1, then lets say a woman is pregnant and she has a 49% chance of dying without an abortion. Should she be allowed to get an abortion? If you believe the 2 are equal, then the answer is no because it's expected that more lives will die as a result of abortion than if birth continues.
The only rebuttal is the belief that a zygote is not equal to a woman, and if woman=human and zygote < woman, then zygote < human.