Is Prenatal Testing for Disease and Birth Defects a Good Idea?

There is a debate among would-be parents and experts alike, as to whether it’s better to undergo prenatal genetic testing and know if there is a problem – or not. Here are the pros and cons.

Expecting a baby can be one of the most joyous times in a couple’s life together. It can also instill a lot of worry. One of the biggest concerns is over the baby’s health. They may worry about birth defects or even genetic diseases. Luckily, most babies are born perfectly healthy. That doesn’t mean such complications are rare, but uncommon. Around one in 33 births result in a birth defect each year, according to the CDC.


Prenatal testing is by and large up to the woman or the couple. There are generally two types: screening and diagnostic tests. First trimester screening usually occurs around 10 to 13 weeks. This includes a blood test and an ultrasound, which can detect whether or not the baby might develop Down syndrome.

During the second trimester a quad screen can be performed. This can test for certain chromosomal indicators which may signal the presence of Down syndrome, along with neural tube defects, or issues with the brain or spinal cord. Keep in mind that even if such testing does come back positive, it doesn’t necessarily mean the child is doomed to a certain condition.

A diagnostic test is usually delivered if there is some sort of family history of a disease, if the mother is of a certain age, if a parent’s medical history puts the baby at risk, or another test unearths a potential problem. This is the only way to know what’s going on for sure. Usually, these are invasive, which is one of the reasons why it has to be considered carefully. In these instances, a sample of the amniotic fluid—known as amniocentesis, or of the placenta—called chorionic villus sampling (CVS), can be performed.

Advancements in medicine have given prospective parents a lot of complex decisions to make, such as what type of prenatal testing should be employed.

Lastly, there is a newcomer to the group: cell-free DNA screening. This is a blood test which examines the DNA of the fetus found in the mother’s bloodstream. It can check for specific chromosomal issues, such as Down syndrome, Tay-Sachs disease, cystic fibrosis, or sickle cell anemia. Though birth defects may occur at any point in the pregnancy, according to the CDC, they are most likely to occur in the first trimester. Currently, there is a debate among would-be parents and experts alike, as to whether it’s better to undergo prenatal genetic testing and know if there is a problem or not. Here are the pros and cons.

PRO:

  • A negative test can allay parents' fears and ease tension.
  • A positive one can help prepare the parents and let them know what to expect.
  • Parents can start saving for the care their child if disability is detected.
  • Testing can allow them to decide whether or not to keep the pregnancy.
  • CON:

  • A positive result can cause the parents anxiety and inner conflict.
  • The stress of knowing can affect their relationship.
  • Those with disabilities today can lead useful, fulfilling, vibrant lives.
  • Genetic screening can give a false positive, causing anxiety for no reason.
  • There may be a chromosomal issue the test misses.
  • Prenatal testing is optional. Some physicians suggest thinking about why a potential parent wants to know before deciding. This could help develop an understanding of whether or not it’s right for them. Dr. Andrea Greiner is a maternal and fetal medicine specialist at the University of Iowa Hospitals and Clinics. She told Live Science that most women don’t undergo such testing to know whether or not to have an abortion, but merely to prepare themselves.

    Some women should evaluate whether or not a positive answer would lead to undue stress, the specialist said. Dr. Greiner also notes that this science is new, and patients should keep that in mind. If you are considering prenatal testing, be sure to ask your doctor a lot of questions before deciding.

    To learn how aging affects pregnancy and prenatal testing, click here: 

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    Yale scientists restore brain function to 32 clinically dead pigs

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    • Researchers at the Yale School of Medicine successfully restored some functions to pig brains that had been dead for hours.
    • They hope the technology will advance our understanding of the brain, potentially developing new treatments for debilitating diseases and disorders.
    • The research raises many ethical questions and puts to the test our current understanding of death.

    The image of an undead brain coming back to live again is the stuff of science fiction. Not just any science fiction, specifically B-grade sci fi. What instantly springs to mind is the black-and-white horrors of films like Fiend Without a Face. Bad acting. Plastic monstrosities. Visible strings. And a spinal cord that, for some reason, is also a tentacle?

    But like any good science fiction, it's only a matter of time before some manner of it seeps into our reality. This week's Nature published the findings of researchers who managed to restore function to pigs' brains that were clinically dead. At least, what we once thought of as dead.

    What's dead may never die, it seems

    The researchers did not hail from House Greyjoy — "What is dead may never die" — but came largely from the Yale School of Medicine. They connected 32 pig brains to a system called BrainEx. BrainEx is an artificial perfusion system — that is, a system that takes over the functions normally regulated by the organ. The pigs had been killed four hours earlier at a U.S. Department of Agriculture slaughterhouse; their brains completely removed from the skulls.

    BrainEx pumped an experiment solution into the brain that essentially mimic blood flow. It brought oxygen and nutrients to the tissues, giving brain cells the resources to begin many normal functions. The cells began consuming and metabolizing sugars. The brains' immune systems kicked in. Neuron samples could carry an electrical signal. Some brain cells even responded to drugs.

    The researchers have managed to keep some brains alive for up to 36 hours, and currently do not know if BrainEx can have sustained the brains longer. "It is conceivable we are just preventing the inevitable, and the brain won't be able to recover," said Nenad Sestan, Yale neuroscientist and the lead researcher.

    As a control, other brains received either a fake solution or no solution at all. None revived brain activity and deteriorated as normal.

    The researchers hope the technology can enhance our ability to study the brain and its cellular functions. One of the main avenues of such studies would be brain disorders and diseases. This could point the way to developing new of treatments for the likes of brain injuries, Alzheimer's, Huntington's, and neurodegenerative conditions.

    "This is an extraordinary and very promising breakthrough for neuroscience. It immediately offers a much better model for studying the human brain, which is extraordinarily important, given the vast amount of human suffering from diseases of the mind [and] brain," Nita Farahany, the bioethicists at the Duke University School of Law who wrote the study's commentary, told National Geographic.

    An ethical gray matter

    Before anyone gets an Island of Dr. Moreau vibe, it's worth noting that the brains did not approach neural activity anywhere near consciousness.

    The BrainEx solution contained chemicals that prevented neurons from firing. To be extra cautious, the researchers also monitored the brains for any such activity and were prepared to administer an anesthetic should they have seen signs of consciousness.

    Even so, the research signals a massive debate to come regarding medical ethics and our definition of death.

    Most countries define death, clinically speaking, as the irreversible loss of brain or circulatory function. This definition was already at odds with some folk- and value-centric understandings, but where do we go if it becomes possible to reverse clinical death with artificial perfusion?

    "This is wild," Jonathan Moreno, a bioethicist at the University of Pennsylvania, told the New York Times. "If ever there was an issue that merited big public deliberation on the ethics of science and medicine, this is one."

    One possible consequence involves organ donations. Some European countries require emergency responders to use a process that preserves organs when they cannot resuscitate a person. They continue to pump blood throughout the body, but use a "thoracic aortic occlusion balloon" to prevent that blood from reaching the brain.

    The system is already controversial because it raises concerns about what caused the patient's death. But what happens when brain death becomes readily reversible? Stuart Younger, a bioethicist at Case Western Reserve University, told Nature that if BrainEx were to become widely available, it could shrink the pool of eligible donors.

    "There's a potential conflict here between the interests of potential donors — who might not even be donors — and people who are waiting for organs," he said.

    It will be a while before such experiments go anywhere near human subjects. A more immediate ethical question relates to how such experiments harm animal subjects.

    Ethical review boards evaluate research protocols and can reject any that causes undue pain, suffering, or distress. Since dead animals feel no pain, suffer no trauma, they are typically approved as subjects. But how do such boards make a judgement regarding the suffering of a "cellularly active" brain? The distress of a partially alive brain?

    The dilemma is unprecedented.

    Setting new boundaries

    Another science fiction story that comes to mind when discussing this story is, of course, Frankenstein. As Farahany told National Geographic: "It is definitely has [sic] a good science-fiction element to it, and it is restoring cellular function where we previously thought impossible. But to have Frankenstein, you need some degree of consciousness, some 'there' there. [The researchers] did not recover any form of consciousness in this study, and it is still unclear if we ever could. But we are one step closer to that possibility."

    She's right. The researchers undertook their research for the betterment of humanity, and we may one day reap some unimaginable medical benefits from it. The ethical questions, however, remain as unsettling as the stories they remind us of.

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