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The Accuracy of Prenatal Genetic Testing

The Accuracy of Prenatal Genetic Testing - When Does Life Begin?

The Accuracy of Prenatal Genetic Testing - When Does Life Begin?Some women and couples terminate because they’ve received undesirable prenatal genetic testing results and want to minimize the pain their child could experience from their diagnosis. However, taking an innocent life—regardless of diagnosis—is wrong, especially when there’s a chance the child could be perfectly healthy. According to MedlinePlus, a service of the National Library of Medicine, “Genetic testing can provide only limited information about an inherited condition. The test often can’t determine if a person will show symptoms of a disorder, how severe the symptoms will be, or whether the disorder will progress over time.”

What do these screenings test for?

Prenatal genetic testing screens for a number of abnormalities, such as chromosomal disorders like Down syndrome and Edwards syndrome (trisomy 18), genetic diseases like cystic fibrosis, and birth defects like spina bifida. 

Prenatal genetic testing involves initial screening with possible further diagnostic testing. Initial screening only indicates the risk of genetic disorders. It does not determine whether the baby actually has a condition. Follow-up diagnostic testing often using amniocentesis looks at whether the baby actually has the genetic condition. Amniocentesis involves injecting a needle into the uterus to withdraw amniotic fluid. The procedure can put both baby and mother at risk of miscarriage, infection, loss of amniotic fluid, etc. Also, the diagnostic tests do not indicate the severity of the genetic disorder if one is found. This is a severe limitation of the testing.

Doctors typically run these tests between the first and second trimesters of pregnancy. Prenatal genetic testing was once not so common; now, over a third of all pregnant American women receive genetic testing. 

False positives in prenatal genetic testing

As the genetic testing industry grows, new testing has become available for rare diseases like DiGeorge syndrome and 1p36 deletion. However, in a recent New York Times investigation, these newer genetic tests have proven to be unreliable.

The New York Times reports that many of the tests screening for disorders like Down syndrome are “very accurate.” However, 80-93% of positive genetic test results for rare diseases are wrong

Fetal diagnoses and abortion 

False positive test results are dangerously misleading, as many medical providers encourage women to abort when faced with an undesirable fetal diagnosis. We use the term “undesirable” because many fetal diagnoses that cause women and couples to abort are not actually life-threatening.

DiGeorge syndrome, one of the rare diseases receiving false positive test results, comes with an average life expectancy of 46 years; even DiGeorge patients with major congenital heart disease have a 72% chance of surviving until the age of 45.

Down syndrome, one of the most common chromosomal disorders found through traditional genetic testing, comes with an average life expectancy of 60 years. By age 31, 34% of people with Down syndrome live independently while 57% work paid jobs.

In many cases, these diagnoses do not prevent people from living happy, productive lives. So, why are medical providers encouraging abortion, even for non-life-threatening conditions? Diagnosis or not, the solution is never to take an innocent life—and you certainly do not minimize one’s suffering via abortion. Most genetic testing occurs between 11-20 weeks gestation, and there is growing evidence to support that fetuses feel pain during these stages of development.

As with adult patients facing short life expectancies, palliative care is available for babies who are terminal to reduce suffering and give them the dignity of natural deaths.

Learn more about the various stages of fetal development (conception, first, second, and third trimester) and don’t forget to follow us on social media (Facebook, Instagram, and TikTok).