When the second purple line appeared on the white plastic wand on a March morning in 2002, I knew next to nothing about pregnancy and even less about raising a child. It was years before I’d go on to cover parenting and pediatrics, and write about sequencing children’s genomes. Yet from the first days of that pregnancy, I was already enmeshed in the most cutting-edge technologies of the time, thanks to my friend Tali, whose son was due a week after mine.
Tali had recently moved to my home state of North Carolina from Israel, where nuchal translucency testing was standard. I had no idea what it was, but I figured it was important, judging by her level of outrage that this test to gauge Down syndrome risk — combination of an ultrasound to measure the collection of fluid under the skin on the back of a fetus’s neck, and a blood draw — wasn’t commonly available in the United States. Within days, she told me that she’d found a doctor who was getting certified to perform the testing. He needed subjects. Tali and I volunteered.
I had signed up blithely, without seriously considering what I’d do if the test result came back positive. I expected good news — and, fortunately, I got it. Now, more than a decade later, nuchal translucency is old hat. Other, more sophisticated tests have begun to usurp what was lauded as the latest in prenatal technology in the early aughts.
Nuchal translucency offered both Tali and me reassurance. But the various permutations of prenatal screening and testing do not always provide comfort. I am witness to that in the heart of midtown Manhattan, not far from Radio City Music Hall, in a clinic where a woman and her husband have just made a life-altering decision. The woman is 40 years old, with high cheekbones and skin the color of toasted almonds. She is 12-and-a-half weeks pregnant with one baby, but minutes earlier, before she sat down with me in an empty exam room, she was pregnant with two.
Her journey to motherhood had not been easy. The twins had been conceived via in vitro fertilization after the woman and her partner had spent more than a year trying to get pregnant the old-fashioned way. A week before, she had had a microarray analysis that peered deeply into the genetic makeup of her twins.
Microarray analyzes fetal cells for countless less apparent disorders that occur when a tiny snippet of DNA has been added somewhere it’s not supposed to be or deleted entirely, revealing genetic hiccups that previously could not be detected prenatally. Some of these changes are meaningless; others may be associated with autism or rare disorders such as DiGeorge syndrome, which is characterized by heart problems and a roughly 25 percent risk of developing schizophrenia.
As the woman explained, “We made use of technology throughout this process, so it would be a shame not to take advantage of this [test]. I wanted to make sure that, given my age, there was nothing wrong.”
She knew that the microarray would reveal all sorts of genetic blips, DNA duplications and deletions too tiny to be seen under a microscope, some of which are associated with worrisome conditions and others of which aren’t understood. The test would also detect major chromosomal problems, of which Down syndrome is the most common.
Even at age 40, just 1 of 100 pregnancies results in Down syndrome. And yet the couple beat those odds: one of the twins was confirmed to have the extra 21st chromosome that causes the condition.
“You don’t think it’s going to happen to you and then here it is. I still can’t get over the fact. Today we reduced the baby with Down syndrome,” the woman tells me, using a common euphemism for terminating one or more fetuses in cases where a woman is carrying more than she intends to deliver. Many doctors call this “fetal reduction.” She reflects on her decision, made possible by these new tests, as she lowers herself onto an exam table to rest. “I look at this as a sign from God. My mother believes in karma. I think this baby was only meant to be for twelve weeks and his suffering was shortened,” she says. She raises herself up on her elbows and looks at her husband. “Then I feel like, ‘Oh my god, I just killed a baby.’ ”
Considering that women have been getting pregnant for a very long time, prenatal diagnosis — the ability to peer inside the womb and emerge with a snapshot of fetal health — is a fairly recent development, a convergence of medical technologies such as amniocentesis and ultrasound with emerging insights about genes and chromosomes. But it’s the legalization of abortion in 1973 that really served as a catalyst for change. After all, without the ability to choose whether or not to continue a pregnancy, knowledge gleaned from prenatal diagnosis would have remained largely theoretical. With the decriminalization of abortion, what to do became a choice.
While there are women who’d never opt for an abortion, it’s disingenuous to ignore the fact that terminating a pregnancy is one possible outcome of earlier, more sophisticated genetic tests. The issue of how people feel about disability and, in turn, how that impacts their decisions regarding abortion is an essential aspect of any discussion about advances in prenatal testing.
Yet abortion remains the elephant in the room when it comes to prenatal testing. When I discuss my work with colleagues and friends interested in the subject, some say, “ You’re not going to mention abortion, are you? My gut tells me that I think you’re walking into a minefield if that becomes a major part of the book.” Others say, “Abortion should definitely be a chapter. How could it not be?”
Much of the prenatal testing conversation centers on Down syndrome because the condition is so well- known, unlike others that affect far fewer people. One of every 792 babies born in the United States has Down syndrome. Compared to many other chromosomal conditions, however, Down syndrome is considered a relatively mild genetic complex. Chromosome 21 is the smallest chromosome, so the extra genetic material that accompanies a third copy is not as massive or overwhelming as it would be had it occurred on another, larger chromosome. The genetic disorder that results from a triplication of any chromosome is called a trisomy. A trisomy 22 baby, for example, probably would not make it to birth.
Starting in the 1970s, various epidemiologists began making the case that standardizing testing for Down syndrome was a public health priority. Since then, screening for Down syndrome has become broadly accepted by the medical community and, in turn, by many pregnant women and their partners. In 2007, the American College of Obstetrics and Gynecology expanded its prenatal screening recommendations to offer all women, regardless of age, the option of screening and diagnosis for genetic conditions, including Down syndrome.
One of the consequences is clear. In 2015, Brian Skotko, who co-directs the Down Syndrome Program at Massachusetts General Hospital, published a comprehensive look at Down syndrome live-birth rates in the United States. Between 2006 and 2010, he and his colleagues calculated that 30 percent fewer babies with Down syndrome were born than were expected, due to elective terminations.
Decisions about whether to have a baby with Down syndrome tend to vary geographically and by level of education. In the 2015 study, abortions for reasons of Down syndrome were highest in the Northeast and Hawaii and lowest in the South. Asians were the most likely to terminate due to Down syndrome, while Hispanics and American Indians were the least likely.
The Rise of Noninvasive Prenatal Screening
Various forms of prenatal testing have been around for decades, but when noninvasive prenatal screening (NIPS) debuted in 2011, its greater accuracy combined with its ease of use contributed to its rapid uptake. In a few short years, NIPS, also called cell-free DNA screening, has become pervasive in the prenatal-testing market. Rather than face off with a long needle or catheter guided through the cervix or abdomen late in the first trimester, or a long needle in the abdomen in the second trimester, a quick venipuncture can collect enough blood midway through the first trimester to gauge whether the fetus’s chromosomes are intact, with high accuracy and no in utero assault. Within a few weeks of a woman learning she’s pregnant, her blood contains fragments of fetal DNA (NIPS actually detects DNA from the placenta, considered a proxy for fetal DNA, that is free-floating in the mom’s bloodstream). The amount of cell- free DNA from the fetus and mother can then be analyzed to predict Down syndrome (and an increasing number of other chromosomal conditions) with up to 99 percent accuracy — though the concept of accuracy itself is nuanced and complex and fluctuates depending on the age of the mother. NIPS, being a blood test, also sidesteps the very small but still scary risk of miscarriage that accompanies CVS (short for chorionic villus sampling) or amnio.
Initially reserved for women over 35, NIPS has now spread to younger women as well, and has spawned a $500 million industry expected to balloon to $2 billion by 2020. But who gets the testing ranges widely, depending upon who goes to the doctor in the first place. Lower-income women, due to lack of access, don’t seek out prenatal care nearly as regularly as more well-to-do mothers. If they do, they’re often too far along in their pregnancies to get screened. Due to geographic discrepancies in Medicaid coverage, NIPS or other tests may not be covered. ...
Despite its high degree of accuracy, NIPS is not perfect. Nor does it equate with a diagnosis. NIPS is a screening test; it can be complicated by a lower-than-expected fraction of fetal DNA and even by an underlying maternal cancer diagnosis. Only CVS or amnio can offer confirmation. But the message is not always getting across to women — or their doctors. Cases have been reported of women coming close to terminating pregnancies they believed were affected based on NIPS results — only to learn that they were not. Experts blame the companies that market the tests for robust advertising that they say misleads patients — and some physicians — into believing that the results are equivalent to a diagnosis. To address misunderstanding, the American Congress of Obstetricians and Gynecologists issued a statement in 2015 stressing that any positive results need to be confirmed via other tests such as amniocentesis. In other words, ACOG emphasizes, a decision to have an abortion should not be based solely on the results of NIPS.
Yet there has been little public conversation about widespread prenatal screening and the “consequences of the transformation of every fetus — and not only the precious fetus produced thanks to complex technological interventions — into an ‘at risk’ entity, extensively tested, measured and evaluated by health professionals,” wrote the science historian Ilana Löwy in a paper about prenatal diagnosis.
In an op-ed in The New York Times, “The T.M.I. Pregnancy,” Patricia Volk lamented that all the testing surrounding her daughter-in-law’s supposedly “normal” pregnancy had left them both feeling “guardedly happy.” She recounted a series of scary ultrasound findings that turned out to be nothing, and mused: “Prenatal science has helped a lot [of] people and people-to-be. But just because a patient can know something, must she? Odds are in this baby’s favor, yet every sonogram adds something scary to the pot. What is one of the most joyous times of life has turned into something ominous and fraught, loaded with the potential to go wrong.”
Yet one person’s anxiety is another’s sigh of relief. The debate over what testing and how much hinges on so many factors. In fact, two letters to the editor in response to “The T.M.I. Pregnancy” highlight why this push-and-pull is one of the great medical and social conundrums of our time. In one, Alastair Pullen describes his experience declining all testing during his wife’s first pregnancy “for all of the reasons this article mentions.” Halfway through the pregnancy, he and his wife agreed to an ultrasound and discovered their daughter had a fatal condition and would not survive long after birth. “Faced with a horrible decision,” Pullen writes, “we decided to induce preterm labor. Becket was stillborn. The only thing worse would have been if we had had no knowledge of her condition.” Pullen had first decided not to test but ended up grateful he changed his mind. He and his wife welcomed testing in later pregnancies; they now have three healthy children, and, he says, “the barrage of testing affirmed our excitement.”
Ingrid Chafee, on the other hand, gave birth when no tests were available. She was shocked when she delivered her firstborn in 1965, only to learn he had hydrocephalus and spina bifida. Surgery repaired much of the damage, but her son — who now holds a doctorate from Oxford — still has physical problems. She concludes: “He has said many times that he is glad that there were no ultrasound tests available at the time of his birth. If there had been, he wouldn’t be here. To know or not to know? It’s up to each to decide.”
Who Is a Gift and Who a Burden?
The ethics of abortion are set to become much more complicated as more women have access to powerful genetic tests such as microarray, for these tests can identify genetic flaws that are not readily understood.
Microarray had confirmed that the almond skinned woman who had the fetal reduction was carrying one twin with Down syndrome. But in the case of more ambiguous genetic errors in a boy named Ryan Docherty, confirmation was the easy part. It was the interpretation — figuring out the significance of the problems that microarray had detected in utero — that proved difficult.
When she was pregnant, Ryan’s mom, Jen Sipress, had a microarray test. You’ll recall that chromosomal microarray analysis can detect deletions and duplications of genetic material — errors that are far smaller than an entire extra chromosome. But just because they’re smaller doesn’t mean they can’t wreak havoc. Some are associated with genetic disorders; many more aren’t associated with anything because they’re so newly discovered or because they don’t appear to be detrimental according to the limited amount of research that exists. Sipress, 42, is a New York City narcotics prosecutor; she thrives on evidence. When her test results came back, the evidence was disconcerting: Ryan, still in utero, had not one but two findings — “variants of uncertain significance” — inherited from his mother and his father. Docherty had passed down a duplication involving six genes, while Sipress had contributed a deletion on chromosome 15 involving four genes. In general, deletions are considered more worrisome than duplications; our bodies can often deal with some extra genetic material, but it’s not as easy to compensate for DNA gone AWOL. To make matters worse, one of the four missing genes had been associated in the medical literature with intellectual and developmental delay. Here’s where things got really confusing: Sipress was missing that same gene and she didn’t appear to be affected at all. She worked hard as the family’s primary income earner, putting drug dealers behind bars. She hadn’t even known she was missing any genes until the microarray results came back. But genes—or their absence — can affect people differently; it’s a phenomenon called “variable expressivity.”
Before the amniocentesis to collect fetal cells for the microarray analysis, Sipress and Docherty had decided that were they to learn that their unborn child wouldn’t be able to live independently as an adult, they would end the pregnancy. When they got the results, they leaned toward abortion. After talking to their doctor, Ron Wapner, author of a New England Journal of Medicine study about microarray’s effectiveness, they changed their minds. As Sipress recalls, Wapner said, “‘I get people coming in here who . . . want to know this is 100 percent fine.’ And he said, ‘I can’t give you 100 percent. I can give you 80 percent.’ And I said, ‘I’m going to take those odds.’ ”
Emotionally, it was a terrible time for Sipress and Docherty. Ryan was their first child, and he had been conceived after two rounds of IVF. But Sipress doesn’t regret finding out. “I don’t understand why even women in their 20s aren’t undergoing this testing,” she says. “Knowledge is power. Doesn’t everyone realize that?”
It’s certainly made for some awkward conversations with her husband’s family in Scotland, who know about the missing genes. “They ask if there is something wrong with the kid, and I say, ‘Technically, yes, but he’s not exhibiting any symptoms,’ ” says Sipress. To that end, Docherty, who stays home with Ryan, is a vigilant observer. “Are we still worried?” says Docherty. “Absolutely.” It’s easy to attribute every behavioral challenge — Ryan’s not a good sleeper, but neither are lots of babies — to the missing genes. Anticipating this, Wapner has cautioned them against engaging in this sort of genetic determinism. “He said, ‘Go about your business. If you feel something is really wrong, then you act.’ To be honest,” says Docherty, “Ryan doesn’t have a problem, as far as I can see.”
To what end are we willing to go to detect disability? Once we find it, is there a dividing line between “good,” or tolerable, disabilities and “bad,” or intolerable, limitations? How do we decide which ones may warrant abortion and which are acceptable? What feels overwhelming to one person— the birth of a child with a genetic disorder— may feel like God’s gift to another. Who are we to judge what — who, more accurately—is a gift and who is a burden?
Get the best of KQED’s science coverage in your inbox weekly.