A fertilized egg is not a life; it is a potential life. Every egg and every sperm is also a potential life. Where a potential life becomes a life is not at conception, but the point at which the fetus is viable outside the womb. To say a fertilized egg is a life that needs protecting, one should also say that an unfertilized egg and sperm are also lives that need protection, and every use of contraception or engagement in masterbation would be the functional equivalent of an abortion. Furthermore, defining life at conception is an unnecessary burden on a woman's right to control her own body. A person can't force another to donate an organ even if that person's life depends on it, because the potential donor has the right to control his/her body. The choice to save a life through donating an organ is no different than the choice to produce a life by providing a womb. The morality behind the choice is irrelevant; there is a constitutional right to control one's body and have the choice to hold or not hold a potential life.