Alex Polyakov, Genia Rozen, Chris Gyngell, and Julian Savulescu recently published an article entitled “Novel embryo selection strategies—finding the right balance,” in which they take a critical attitude toward the use of what they call “novel embryo selection strategies.” In this article, they discuss problems with fluorescence in situ hybridization (FISH), preimplantation genetic testing for aneuploidy (PGT-A), and a novel form of culture fluid testing. While polygenic embryo selection is not discussed in depth, the authors consider this a novel technology.
The authors propose the argument that “relying on novel technologies to prioritise embryo transfer is ethically acceptable, but discarding embryos based on these unproven technological advances is not.” They continue, “[i]n other words, we must strive against overconfidence to ensure that novel technologies do not result in unintentional overall harm.” While aiming to avoid unintended harm is clearly a worthwhile goal, their conclusion that discarding embryos based on “novel” and “unproven” technologies is not ethically acceptable is mistaken.
Polyakov et al.’s ethical claim is based on two commonly proposed rational criteria for selection strategy: (1) “the shortest possible time to pregnancy” and (2) “the prevention of children being born with conditions that will significantly adversely affect the length or quality of their life” as well as an additional criterion they propose that (3) “the overall chance of pregnancy from a stimulated IVF cycle (which can be termed ‘cumulative live birth rate per stimulated cycle started’) must not be reduced by a novel selection strategy, compared to the currently accepted selection/deselection criteria.” The authors believe all three criteria must be met for an embryo selection strategy to be acceptable.
The authors provide historical examples of fluorescence in situ hybridization (FISH), PGT-A, and a novel form of culture fluid testing used by an IVF clinic in Victoria, Australia. Regarding FISH and PGT-A, the authors express concern about potential harm and reduction in the probability of successful pregnancy as a consequence of the embryo biopsy. However, the authors’ primary objection is that, in their view, premature adoption of these novel technologies resulted in excess of false positives, which resulted in couples having their chance of pregnancy per cycle reduced, a violation of their third principle.
While one response could be to critique the authors’ historical examples, there is a deeper issue. Even if their evaluation of the evidence is correct, the authors’ criterion for an ethically acceptable embryo selection is flawed. Strict adherence to not reducing the probability of a successful pregnancy per cycle can produce incorrect moral judgments when considering the trade-offs between a successful pregnancy and the well-being of the future child.
Consider the following extreme scenario to illustrate this point: a novel embryo testing technique is used to detect the presence of a genetic variant that inflicts tremendous suffering on all its carriers. The test has a 99% sensitivity (true positive rate) and 99% specificity (true negative rate). Since the test is not perfect, it may result in some instances in which a couple decides to undergo further IVF cycles despite the available embryo(s) having normal reproductive potential and not actually harboring the undesirable genetic variant. Nevertheless, the use of this test is clearly morally permissible despite failing the third criterion.
Less hypothetical is polygenic embryo screening, which would classify as a “novel” approach. This new technology may motivate some couples to undergo additional IVF cycles to get healthier children despite having viable embryos of average health available. Is this so bad? If couples are fully informed of the expected benefits, and downsides of a novel technology, and some decide to undergo additional cycles in an effort to have healthier or happier babies, it seems wrong to regard the method or the couple’s choice as morally unacceptable.
The authors also express concern about not enough information being provided after a couple has their embryos deemed—often incorrectly—as abnormal. They go so far as to say, “[t]his not only results in a possible increase in the need for further stimulated IVF cycles for these patients but also impinges on their reproductive autonomy.” It seems odd that Polyakov et al., who express concern about reproductive autonomy, simultaneously believe that “[d]iscarding embryos based on unproven technologies must not be permitted…”
Why not provide couples with all relevant information and then let them make a voluntary choice? If they undergo additional cycles while fully informed, that hardly seems morally objectionable. In fact, choosing to undergo more cycles after using polygenic screening in an effort to have a healthier child is far from unethical. It is laudable.
The medical risk-benefit calculus changes when people choose to do IVF for the sole purpose of undergoing PGT-P (still unvalidated and of limited utility) as opposed to adding PGT-P to patients already undergoing IVF for purposes of infertility or PGT-M. Additional ethical issues include who pays for it? And if it’s the patients themselves, who would have access to the technology? I understand that this latter point is not different than the situation with IVF in general in the U.S. and many parts of the world today. Still as long as patients are counseled appropriately, they should have the autonomy to make that choice. As a physician though, I would in general not actively recommend a procedure with known potentially significant risks (IVF) for purposes of a technology with unproven benefits (PGT-P).
“...relying on novel technologies to prioritize embryo transfer is ethically acceptable, but discarding embryos based on these unproven technological advances is not.”
I'm afraid this is an argument long since made irrelevant by public policy. In most of the world abortion is legal for any reason or no reason. Abortion in this case being inflicted most often on a viable--implanted the old way--fetus of some duration, not a blastocyst (or in vitro fetus)--and for those we have the "morning after" pill or in this case, the trash can.
Science gave us the the ability of life over death (really visa versa). Politics decided the legal uses of the science. it's too late for your moral concerns now. Deal with it. It's really the parents' "moral" concern at this point. Welcome to Huxley's "Brave New World".