August 2024

The Ethics of Prenatal Genetic Testing

Is more information better when it comes to prenatal screening?

Summer 2024

  • by Molly McDonough
  • 7 min read

Vardit Ravitsky

Vardit Ravitsky

When Vardit Ravitsky was pregnant at age forty, a routine screening test revealed a 1-in-40 chance her child could be born with Down syndrome. Suddenly Ravitsky, senior lecturer on global health and social medicine, part-time, at HMS, faced a dilemma: Was it worth undergoing further invasive testing, risking miscarriage, to find out for certain?

A bioethicist who focuses on reproductive technologies, Ravitsky already understood the nuances of genetic testing. “I had access to the best genetic counseling in the world,” she says, “but it was still an excruciating experience.”

Ravitsky and her husband were offered exercises to clarify their risk perception: Imagine a 1-in-40 chance of winning the lottery. Does that sound promising? Imagine you’re boarding a flight knowing there’s a 1-in-40 chance the plane will crash. Does that seem like a high risk? “These decisions are so contextual, so personal,” says Ravitsky, who is president of the Hastings Center, a nonprofit bioethics research institute. “And in a pregnancy, you’re making them under time pressure, about the most precious thing in your life.”

Since Ravitsky first faced that decision years ago, scientific advances have made choices like these even more complex. Prenatal genetic testing — including noninvasive prenatal testing, or NIPT — provides more information about the fetus. And people undergoing in vitro fertilization can opt to screen embryos for many genetic conditions and traits, deciding which to implant based on the results. Some private companies have started offering polygenic embryo screening, which combs through an embryo’s genome to evaluate the risk of common diseases like diabetes or depression and could potentially even classify embryos based on traits like intelligence, height, and skin color.

One-quarter to one-half of pregnant individuals in the U.S. now opt to undergo NIPT, which screens for genetic disorders by analyzing small fragments of fetal DNA circulating in the pregnant patient’s blood as early as nine or ten weeks into pregnancy. For many conditions, these tests are still quite uncertain; they’re meant to screen for risk rather than to diagnose, and false positives are common. Yet studies have found that pregnant people make critical decisions based on the results.

Harvard Medicine Associate Editor Molly McDonough caught up with Ravitsky to discuss how genetic tests like NIPT can contribute to the uncertainty facing expectant parents and the ethical issues that arise when we make decisions based on challenging calculations of risk. The interview has been edited for length and clarity.

We live in a time of increasing access to genetic information about embryos and fetuses. As a bioethicist, what interests you in these technologies?

For thousands of years humans had babies with zero access to information until birth. From a historical perspective, this whole notion of knowing ahead of time is novel — but it so quickly became a part of our culture to expect it. Beyond genetic testing, even ultrasound represented a huge cultural shift. To see the fetus before birth changed our relationship to it, emotionally and socially.

When you don’t know anything about the fetus until birth, there are no ethical tensions; you’re just faced with the outcome of the pregnancy. But having the information introduces ethical dilemmas. When you start selecting who gets to be born, you’re creating a “threshold of entry.” You have a new tool for controlling the composition of society, and that immediately raises concerns about eugenics and who gets to decide.

It’s interesting how ethical considerations seem to shift once I zoom out from my individual perspective. During my pregnancy, I didn’t hesitate to undergo NIPT, because it felt empowering to have the information. But once I start thinking about implications at the societal scale, it feels more problematic.

Any type of program meant to give people information prenatally must have the objective of enhancing reproductive autonomy. It must be about choices and knowledge; it should not slip into the goal of eliminating certain types of conditions or even certain traits, syndromes, or types of people. What child to have should always remain a personal decision, free of societal pressures.

But even if having information about genetic risk is empowering for the individual, it can introduce a host of additional ethical issues.

Exactly. We live in a very strong culture of “knowledge is power.” In a paper we published in 2016, we asked, “But what is knowledge?” If it’s an avalanche of information you can’t really fully understand and that forces you into a corner to make ethically fraught decisions under time pressure, is it power, or is it also something else?

NIPT is one example of this. It can test for so many different conditions, many of which you’ve probably never heard about, with different levels of risk and reliability for each. If your test comes back high risk for a condition, you have to understand the context. High risk based on what population? Based on what measure? How do you make the decision about what justifies more invasive testing? Do you want to live with that knowledge for the remaining months of your pregnancy?

NIPT is a great technology, and survey after survey shows that women want access to it. But as a bioethicist, I look at what it does to individual pregnant people and to society. It leaves us with so much challenging uncertainty. And that is very concerning.

How can clinicians support patients facing these kinds of uncertainties?

We need to develop good tools for presenting risk and train clinicians to use them. Risk is notoriously difficult to communicate and to process, because it doesn’t tell you what will happen to you. The better tools we have for communicating the information, the better job we can do with counseling.

Clinicians also need to be very careful in how they present information, to refrain from charged and biased framing. In the case of Down syndrome, for example, there’s literature showing that counseling is often not neutral, that high-chance results are presented as “bad” news, as a decision about termination, rather than saying, “Your fetus seems to be healthy and it has trisomy 21,” which is a totally different framing. A discussion of what it means to raise this child should always come first.

Moreover, some of the conditions NIPT detects are not really diseases. We argue over what to call them — conditions? traits? disabilities? — but some disability rights advocates argue they should either not be included or should be distinguished from diseases. In those cases, the counseling should be particularly sensitive and balanced, considering that with some disabilities the issue is not so much the physical limitation as it is the socially constructed barriers to opportunities.

The more we train clinicians to use neutral language and to present chances, risks, and benefits in a balanced way, the better job we’ll be doing. There are genetic counselors, bioethicists, and advocates dedicating their lives and careers to producing this information. There’s research on how to present information about risk more effectively. But we have a real barrier translating all this to the clinic. Implementing this advanced body of knowledge and integrating it into medical education is a huge challenge.

In the meantime, your research shows that many patients turn to online discussion boards like Reddit seeking guidance through the uncertainty these tests can introduce.

Patients want emotional support that we often don’t provide very well, and they want to hear how other people thought through these decisions. It can be beneficial to hear from other people — what values they engaged, what were the tensions, what conversations they had with family and friends, or just hearing that it’s OK to have doubts and conflicts.

The great concern about turning to a platform such as Reddit is that you’ll get misinformation. It’s not disinformation in the sense that bad actors are on there to mislead you intentionally. But patients sometimes leave their doctor’s offices with misunderstandings regarding the tests that they then share, or they share other things they read online.

The one-on-one model of “I’ll sit with you and go over the dozens of conditions that NIPT can detect and explain the level of risk for each and what it might mean for your child” is unsustainable. So electronic resources, interactive tools, maybe social media platforms, video education for patients, more training for clinicians — that’s the way of the future. But even all of that, if it’s successful, will still leave people with anxiety and uncertainty.

In our current political landscape, many of these issues are fraught with controversy. How do you navigate researching and engaging publicly with such sensitive topics?

As a bioethicist, it’s my job to formulate normative arguments. And you have your personal convictions and cultural background, of course, so it’s important to be transparent about where you come from. I’ll say, for example, “I’m arguing in favor of protecting access to IVF. Here’s why.” But what makes it legitimate is that other people can then respond and say, “Your argument was flawed here” and we can improve the discourse by exploring the pros and cons. The key to bioethics is that open, informed, inclusive exchange.

When things are really controversial — the status of embryos, pregnancy termination, and so on — it’s beneficial to stay focused on promoting women’s health. If certain policies are proven to lead to bad outcomes, to higher maternal mortality rates among Black women or increased incarceration of pregnant women, for example, these are measurable. When we pay attention to health outcomes, we’re on less controversial ground, because we are staying close to how policies impact the health and well-being of women and families.

 

Molly McDonough is the associate editor of Harvard Medicine.

Image: Flynn Larsen