There is no inclusive logical or rational standard based on scientific evidence that can de-humanize a human child in the womb that also will not dehumanize humans elsewhere.
This is because humans are humans, life is life, and viability either is or it is not.
Those who still choose to seek out such excuses are infected with the ideology of relativism, instead of working through the world we know based on its definable and approachable scientific absolutes.
In the US, there is no federal definition of life, as it has always been assumed (legislationally) that human beings start inside the womb. This precedence was brought in from Europe, and can be traced back thousands of years into very well-known civilizations (like the Grecian and Roman empires), and is still present today in state-based legislation, such as the murder of a pregnant woman being a double homicide.
The US federal government does not have the authority, based on the constitution, to define human life, which is where Roe Vs. Wade gets its power. To change this, it would need to be amended.
In a nutshell, that power was given to the people to define, and optionally the states to choose to legislate if necessary.
Ultimately, raw capitalism took charge and used big-money to get the US supreme court to rule in favor of Roe vs. Wade, thus removing the thousand-year-old, western-world precedence of life starting in the womb, and setting the new judicial precedence to allow a woman to choose to individually define her baby as a life or not. This is the real freedom (not right) that feminism gave to women.
The states, however, actually have the authority to trump a citizen's freedom, and as there is no legislational standard in the constitution, the Supreme Court cannot declare a state law that defines when life begins unconstitutional. This means it cannot re-enforce Roe vs. Wade over any state that defines life.
Thus, forgetting the marketed hype, misdirection that focuses on women's "rights," and emotionalism that so many have in fearing fringe cases (rape, incest) will also be forced to submit to the law, this all comes down to whether or not the states have the legislational authority to define life, and then defend that life.
They do on both accounts, and history has shown us logic and science define life is life, thus eliminating the exclusive perceptions of irrational thinking that attempt to dehumanize us based on the whims of human fear and arrogance.
— Micah