I’m late to the discussion, sorry. To try to answer the question posed in the post: : … what in your educated scientific opinions, is wrong with Roe"?
I think what is wrong in the first place is legal/Constitutional. The opinion relies on “rights” which are not included in the Constitution. They are, thus judge-created out of whole cloth and ought to have no place in Constitutional construction. An honest opinion would have said this is not a matter of Constitutional interpretation, since the document is silent as to abortion and the science is not within this Court’s competence. There is no federal question. It is therefore a matter for majority rule within the legislative power of the several states.
Strictly scientifically, “viability” is dependent on the state of medical knowledge and expertise, constantly in a state of change. The notion that a right conferred by the Constitution can in any way depend on the state of medical art is cognitively dissonant, to say the least. Such a decision trivializes the very concept of what a “right” is.
When legislatures wrestle with these issues, they may be well advised to explicitly recognize the arbitrariness of limits they set as to the stage of pregnancy beyond which abortion is not permitted. Among the considerations is the extent to which such rules are enforceable, when early abortions may be accomplished by simply ingesting an oral abortifacient.
As well, legislatures ought not permit rare exceptions - like pregnancies resulting from rape/incest - to swallow the rule. There are virtually no valid medical indications regarding health of the mother which require abortion after 15 weeks. The demand for abortion at term is absurd. Most of the risks to the mother have already been incurred by merely carrying the pregnancy to term. Either a vaginal delivery or Cesarean section adds de minimus additional risk compared with delivering the head (the most risky part of vaginal delivery) and performing a “fetal craniotomy” i.e. killing a fully-formed human infant by sucking its brain out of the cranial cavity. I submit that one single video depicting this procedure - shown to the public - would be seen as so shockingly gruesome, inhumane and evil as to immediately eliminate all such demands - no matter how loudly it is depicted my the MSM as “disinformation”.
As to the question of when a fertilized ovum becomes a human individual to which legally -cognizable rights ought to attach, I think the spectrum in which this must be analyzed is in the dimension of information content. A zygote has the entire genetic information required to form a unique human person. It is thus a unique potential person. With in utero development over time, that genetic information is expressed as tissues and organs develop, including the brain which begins to accumulate and process information. This organ informs that particular individual’s life experience by recording information and eventually making much of it accessible to awareness. This is a continuous process and birth - leaving the womb - merely allows the new person a wider variety of sensory input.
In terms of accretion of the information which confers non-genetic individuality on this individual, the notion that birth is the major milestone it has heretofore been seen to be, loses much of its power. From a rational, informational standpoint a unique series of life experiences adds to the new individual’s already unique genetic structure and thereby it IN - FORMS that individual. Birth permits a quantitative - but not qualitative (all the sense organs are working to some extent in utero) - increase in the diversity of that input to the brain. In sum, the uniqueness of an individual begins with the genetic information of the zygote and grows continuously throughout succeeding development, indeed throughout the entire life of the individual. Scientifically, I believe it is essential to consider the informational content as of the essence as to what constitutes a unique individual. Further, this occurs on a continuum and the only landmark which withstands rational analysis, in that regard, is development of the brain which stores and processes the individual’s unique experiences of life. Once that brain becomes even minimally functional, the gathering of individual information increases exponentially. Now, heartbeat is more easily observable and measurable (and emotional). The heart is just a pump, however, whose function is hardly unique. Initial function of the brain, by comparison, is a far more rational definition of the beginning of a unique human individual life. This may or may not be presently amenable to remote sensing from outside the mother’s body. If not today, then likely it will be in the future. That may be a better answer as to “when does ‘life’ begin”? That question, thus, has layers of answers, as a zygote is already alive and it is obviously human. That’s all I have to say about that.