How Early Can Birth Defects Be Detected?

Have you wondered by now how early can birth defects be detected? If not, maybe it`s time you do, especially if you are planning to have a baby.

How Early Can Birth Defects Be Detected

How Early Can Birth Defects Be Detected?

The screening performed during the first trimester of pregnancy consists of a combination of several tests performed between the 11th and 13th weeks of pregnancy. These tests are carried out to find certain structural or functional abnormalities related to fetal heart or chromosomal disorders, like Down syndrome. This particular screen will generally include an ultrasound and a maternal blood test.

Ultrasound: An ultrasound will create images of your baby. This test performed during the first trimester of pregnancy will look for additional fluid behind the neck of the baby. If there`s an increased amount of fluid found with this test, we may very well talk about a heart defect or chromosomal disorder in the fetus.

Maternal blood screen: This is nothing more than a simple blood test. The test will measure the levels of 2 particular proteins: pregnancy associated plasma protein A (PAPP-A) and human chorionic gonadotropin (hCG). If the levels of the proteins are too low or too high, again, we may talk about chromosomal disorders being involved.

Medical Examinations

The pregnant woman can perform a double, triple or even quadruple test (mostly available in private clinics) which can measure 2, 3 or 4 biochemical parameters in the mother`s blood. No matter of the type of test chosen by the pregnant woman, she needs be aware the she won`t be able to detect all the birth defects in this manner. The results of the tests take into account the values of the parameters that are measures, as well as the pregnant woman`s age and the risk of genetic abnormalities. If she receives a positive result in this test, this won`t mean that the fetus has a malformation, but rather that he has an increased risk of malformation. However, only by using this indication, the expert will be able to direct the pregnancy to other investigations, like amniocentesis, which can offer a more certain diagnosis.


When one of the future parents or a close relative has a hereditary disease, it`s essential to have a genetic counseling before attempting to conceive a child. This way, the fetus`s risk of inheriting the genetic abnormality can be assessed and the therapeutic behavior for the 9 months of pregnancy can be clearly established. This type of tests should also be performed when the parents already have a child with a genetic defect, when the woman has previously had a miscarriage or when the future mother has more than 35 years.


The experts cannot determine the causes of each and every abnormality with accuracy. In most cases, there are a few causes. Genetic malformations and environmental factors are among the essential causes, which include drugs or toxic substances. There are abnormalities that simply occur without any obvious environmental concern or genetic determinism as well.


A significant proportion of neonatal malformations are attributed to pregnancy that aren`t investigated or investigated when it`s too late in the third trimester of pregnancy. Because of this, it`s essential to diagnose malformations as early as possible.

Interrupting the Pregnancy

If the abnormality is detected by the week 28 of pregnancy, the woman may choose for the therapeutic interruption of her pregnancy. However, the limit to which a therapeutic abortion can be performed isn`t legally outlined; it`s rather an unwritten convention. This particular limit mostly varies from one country to another and might depend on the technology available to hospitals in that particular country. Last but not least, the ethical problems involved in giving up a pregnancy are also taken into consideration. In a lot of cases, a pregnancy that presents an abnormality incompatible with life might stop from evolving, causing what is known as miscarriage.

What about Amniocentesis?

This analysis follows the extraction of amniotic liquid for analysis. The test is performed by simply inserting a needle inside the uterus, and the obviously into the amniotic sac. It doesn`t last for too long and it`s done using local anesthesia, so the sting isn`t felt at all; however, a specific pressure is felt on the uterus at the time of extraction.

It`s an analysis especially recommended for women of more than 35 years old or for those who have bi-test result out of normal. It`s good to perform bi-test before, and then amniocentesis is recommended depending on the outcome. The more we move from the age of 35, the more likely it`s to recommend this particular analysis, which as a matter of fact is a diagnostic, not a screening.

Can You Tell Birth Defects from an Ultrasound?

Ultrasound cannot detect all issues that involve a future baby. Generally, ultrasounds are able to detect a few types of birth defects that might be discovered at weeks 19 – 20 of pregnancy. Most often, these birth abnormalities include some severe heart defects, absence of a limb part, kidney issues, spina bifida or a few cases of cleft palate.

On occasion, ultrasounds may show things of uncertain or even minor significance, but it might not be able to tell while pregnant whether the baby has a problem or not. Although this particular uncertainty might cause some sort of anxiety, the doctor will be able to provide the necessary support and information to get through.

Although ultrasounds can generally show the gender of a baby, they aren`t always 100% accurate. The decision whether or not you want to know is entirely yours.

How Do They Do Genetic Testing during Pregnancy?

If they decide for genetic testing before giving birth, women might decide for chorionic villus sampling or amniocentesis. There`s a blood test that is available for pregnant women to detect a few disorders as well. If these blood tests find a possible issue, chorionic villus sampling or amniocentesis might not even be required. Chorionic villus sampling is generally done between the weeks 10 and 12 of pregnancy, while amniocentesis is done between the weeks 15 and 20.

8 Reasons Why the Doctor Will Recommend Genetic Testing

Your doctor may recommend you to do genetic counseling for the following reasons:

  1. If a couple is planning to start a family and someone in the family has an inherited disease.
  2. One of the parents has already a child with a serious birth abnormality.
  3. The woman has more than 34 years.
  4. The pregnant woman has had at least 2 miscarriages.
  5. A child has medical issues that seem to be related to a genetic syndrome.
  6. The pregnant woman has given birth to a stillborn child who had physical symptoms of a genetic disease.
  7. A regular screening test had a result that was abnormal.
  8. A child has medical issues which may be genetic.
Image courtesy of medindia.net

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  1. crorkservice May 11, 2022

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