How Early Can A Paternity Test Be Done?

Whether you are looking for your family members, or trying to find out the lineage of a child, friend or yourself, DNA tests are a great way to uncover the truth.

These tests use genetic material such as saliva using swabs, which are tested in a lab to determine whether there are DNA matches or connections somewhere in the family tree. 

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One of the most popular and common of these DNA tests is the paternity test. So, let’s take a look at the paternity test, what they are, how they are done and how early they can be done. 

How Early Can A Paternity Test Be Done

What Is A Paternity Test?

Paternity tests are the most popular way to find out the paternity of a child in the case that the biological father or ‘real father’ is contested or in question.

This can be done whilst the child is in the womb, or after birth, and later on in life as long as you have a sample from the child, and from the father in question. 

A paternity test is a type of DNA test that is used to determine the fatherhood of a child or person. A paternity test is a scientific and accurate method of determining the biological father of a child or adult.

These tests typically use cheek swabs, and will need the swab of the potential father and the child to see whether the DNA matches.

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How Is A Paternity Test Done?

For the most part, a paternity test is done by collecting small DNA samples such as swabs from the child and the alleged father.

Sometimes, the mother’s DNA is also collected so that the laboratory can create a comprehensive picture and profile of the child’s DNA to compare and determine whether the child is born of the alleged father. 

A child inherits 50% of the mother’s DNA and 50% of the father’s DNA, so half of each biological parent. Because of this, when the child’s own DNA is tested, it will be easy to determine whether any of the DNA matches that of the biological father, because half of the child’s DNA will be the same as the father’s. 

How Early Can A Paternity Test Be Done?

Technological advancement means that accurate testing can be done during a pregnancy to determine the father of a baby. This can be done very quickly in the pregnancy and poses little to no risk to the mother or the child.

Paternity testing can be done incredibly early to determine whether an alleged father is a biological match or not.

This type of testing is done by testing the fetal cells whilst the mother is pregnant, and by comparing these to the mother’s and father’s blood cells to see whether they match. This type of paternity test can be conducted as early as 9 weeks into the pregnancy. 

In addition to this, a paternity test can be done whilst the mother is pregnant through chorionic villus sampling, where tissues from the placenta are taken and tested against the potential father’s DNA. This test is not as common as it can carry a slight risk of miscarriage or pregnancy loss. 

Also, an amniocentesis can be performed to determine the father of a child by a professional, who will draw some amniotic fluid, and test this against the DNA sample from the mother and potential father.

These types of tests can be done sometime between the 15th and 20th week of pregnancy. This is considered safe but can sometimes slightly increase the risk of a miscarriage. 

Due to these increased risks, it is often more desirable for mothers to test the paternity of the child after it is born. However, it is not uncommon for the first DNA paternity test to be done, just eight weeks into the pregnancy as it poses a very small risk.

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man taking a DNA paternity test

How Accurate Are Paternity Tests?

How accurate paternity tests are depends on the type of test done and whether it is done professionally and without any mistakes. That being said, most paternity tests are incredibly accurate. 

As mentioned above, a child is created with 50% of its mother’s DNA, and 50% of its father’s DNA, which is why children inherit qualities from both of their biological parents.

When a paternity test is done, swabs and samples will be taken from both the child and alleged father, and sometimes the mother to create a DNA profile for the child. 

This profile will then be compared to the alleged father to see whether there is a biological DNA connection between them.

Due to this fact, paternity tests are highly accurate and produce results with a very high probability of paternity usually of about 99.99% when there is a DNA match.

This is for the common swab paternity tests, as the results for pre-birth paternity tests are slightly different, but still accurate.

For example, a paternity test that is done before the child is born involves taking a blood sample from the mother, and from the father, and comparing this DNA blood sample to the fetal cells. 

This creates a genetic profile, and the fetal cells will be compared to the mother’s blood and the father’s blood to see whether it matches the alleged father’s.

These tests are around 99% percent accurate and can be performed very early into a pregnancy to determine the father of the child. 


To summarize, paternity tests are a very accurate and conclusive way to determine the father of a baby or child. Whilst they can be done when the child is born, or even after they have grown up to test their DNA against the alleged father’s, the test can also be done before the baby is born, incredibly early in the pregnancy, and can be done just after the 8th week of pregnancy. 

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