Is embryo screening eugenics? The history, the science, and the real concern

The word "eugenics" gets thrown at embryo screening a lot. It's a serious accusation, and it deserves a serious answer, so here's the strongest version of the charge: screening embryos for genetic disease risk is, functionally, the same project that led to forced sterilization programs in the early twentieth century. Choosing one embryo over another based on genetics is ranking human lives by their DNA.

That's the claim. And it's wrong, but not for the reason most people think.

The easy rebuttal is "it's voluntary, so it's not eugenics." True, but it doesn't go far enough. The deeper problem is that "eugenics" is doing double duty as a word. It borrows the moral horror of state-coerced sterilization to express a completely different fear: that parents will treat their future children like customizable products. Those are two different concerns, and mashing them into one word makes both harder to think about.

What eugenics actually was

In 1927, the United States Supreme Court ruled in Buck v. Bell that the state of Virginia could forcibly sterilize Carrie Buck, a young woman committed to a state institution. Justice Oliver Wendell Holmes wrote the majority opinion: "Three generations of imbeciles are enough." This wasn't a fringe ruling. Over the following decades, more than 60,000 Americans were sterilized against their will under state eugenics laws. Nazi Germany cited American eugenics programs as inspiration for its own.

The defining feature of historical eugenics wasn't genetic knowledge. It was state coercion. Governments decided who could reproduce and who couldn't, enforced through law and violence, in service of an ideology about racial and genetic "fitness." The target was living people. The method was force. The supposed beneficiary was always the state or the "race," never the individual.

That history matters. It should shape how we think about genetics and reproduction today. But the comparison to embryo screening breaks down on every dimension that made eugenics a moral catastrophe.

PGT-P is voluntary. Parents initiate it, direct it, and can walk away at any stage. No government mandates it. No institution forces it. It operates on embryos already created during IVF, not on living people. And its entire purpose is giving parents information about disease risk so they can make their own decisions about their own family's health.

The beneficiary is the child, not the state.

Calling PGT-P "eugenics" because it involves genetic information in reproductive decisions is like calling a blood donation a stabbing because both involve needles. The mechanism overlaps. The intent and the outcome don't.

The concern behind the label

So if the historical comparison doesn't hold up, why does the word keep getting used?

Because the real fear isn't about Buck v. Bell. It's about Silicon Valley. When people call embryo screening "eugenics," they're usually picturing tech entrepreneurs trying to optimize their children's IQ, not state-mandated sterilization programs. According to survey data, the public's top concern about polygenic embryo screening isn't coercion. It's "parental false expectations about their children" (Ishii 2026). The fear is about commodification: parents treating a future child like a product to be configured.

That's a legitimate concern. It deserves to be taken seriously on its own terms, without the borrowed weight of forced sterilization.

And the public already draws a clear line here. Seventy-two percent of Americans approve of screening embryos for disease risk. Only 36% approve of screening for behavioral traits. People intuitively separate health screening from trait optimization. The eugenics label erases that separation.

Bioethicist Robert Resta asks whether it's "worth tens of thousands of dollars to have a blue-eyed kid who is an inch taller" (Resta 2026). That's a pointed question, but it describes a product nobody is offering. Health-focused screening reports disease risk. Eye color and height aren't part of the conversation.

Capalbo et al. (2024) raise a more precise version of the concern: that "rank-ordering future offspring on the basis of genetic qualities" could "support an ideology legitimizing value judgements based on one's genetic makeup." But reporting absolute disease risk for conditions like type 2 diabetes or breast cancer isn't a value judgment about genetic worth. It's health information. Same category as a cholesterol test or a family history questionnaire.

The disease-versus-trait distinction holds today. But what if it doesn't stay there? If health-focused screening drifts toward trait optimization, the picture changes. That version of the slippery slope argument deserves a direct answer.

Honest about the hard part

Could health-focused screening drift into trait optimization and start to resemble positive eugenics in motivation, if not in method?

Yes. That tension is real, and dismissing it would be dishonest.

Lazaro-Munoz et al. (2021) put it well: "An important legacy of eugenics should be an awareness that arguments from beneficence can serve as cover for less laudable intentions." Voluntariness alone isn't a sufficient answer. The question is what safeguards actually exist.

At Herasight, we lead with disease risk because that's where the evidence is strongest and the ethical case is clearest. Our reports show absolute risk estimates, not relative reductions that can be spun to look more dramatic. Every client works with our counselors, who help interpret results for their family's specific situation. And we've published our ethical framework because the answer to "can we trust you?" shouldn't be "just trust us." It should be something you can read and evaluate yourself.

The data matters here too. Our within-family validation (Moore et al. 2025) tested 17 disease scores on sibling pairs, and 16 of 17 showed no decrease in predictive performance. That's relevant to the eugenics question because it shows the screening actually works for disease risk. If the scores didn't predict disease within families, the whole ethical argument would be academic.

They do. And it isn't.

There's also a biological reality that cuts against the designer baby scenario. The genome isn't a menu. Higher polygenic scores for cognitive ability are linked to increased Parkinson's disease risk (Ishii 2026). These genetic trade-offs, called antagonistic pleiotropy, mean that "optimizing" for one trait can worsen another. You can't engineer a perfect child through embryo screening even if you wanted to. The biology won't cooperate.

Soni and Savulescu (2021) argue from the other direction: "It could be considered unethical not to use this technology as it would offer future generations the prospect of healthier lives." That's a strong claim, and we wouldn't go quite that far. But the underlying logic is sound. If you can lower your child's risk of serious disease using information that's already available, the case for doing so is at least as strong as the case for prenatal vitamins or choosing a school district.

Does giving your child the best shot at a healthy life show a lack of true affection? We think it shows the opposite. Parents move across countries for economic opportunity. They work extra shifts to afford better schools. Wanting to lower your child's risk of diabetes or heart disease is the same impulse expressed through a different kind of information.

The eugenics label borrows horror from a history that doesn't apply and uses it to shut down a conversation families deserve to have. What kind of health information should parents have access to, and how should it be used responsibly? Those are the questions worth asking, and they have better answers than a single loaded word can offer.

If you're interested in learning more about how Herasight's screening works, or you'd like to talk through what it could mean for your family, please reach out to our team.