Yes, infertility medicine will be affected, and treatments for potential parents who carry the genes for devastating diseases. If a “right to life” is granted at the moment of fertilization, IVF and PGT (preimplantation genetic testing) are impossible. No fertility clinic is going to be able to operate under the threat of murder charges for discarded blastocysts and embryos. Nor will infertility and PGT specialists want to transfer weak, damaged or genetically faulty blastocysts/embryos into women’s uteruses.
IMO, any state considering personhood of fertilized eggs is headed for dystopia. I would not want my kids in college there for their sakes, but also because I don’t see how they will attract decent professors who want to be there. Imagine you went the hard and competitive road to earn a PhD and get a job as a professor. Now, you want to start a family, but you find out that you and your husband both carry the gene for Tay Sachs (which runs in my family—my sister has it). You do not want to risk watching your beautiful baby slowly deteriorate, regressing, having seizures, suffering until they die as a toddler. So, you decide to do IVF. Your eggs will be retrieved and fertilized in a lab, then tested with PGT. Only the strongest of the blastocysts lacking the gene will be considered for transfer to your uterus. But if you live in a state with prenatal personhood, you will have no options other than risking Tay Sachs or moving.
Maybe these states will exempt IVF/PGT from their laws by saying that a blastocyst/embryo only has a right to life when it is already in the mother. This would be extremely hypocritical.
Infertility is very common. It’s also likely that one or two of my kids and their cousins are Tay Sachs carriers. Having control over their fertility, and healthcare while pregnant, is a top priority for all of them. Two of them are also gay/bi. They would rather go to community college and transfer, or choose the cheapest in-state option, than feel their options in family planning will be curtailed by state laws.