Prenatal Paternity Test – What Options do I have?

Why should you have a prenatal paternity test, and if you decide to have one, what type should it be? These questions are distinctly different, so should be addressed one at a time, although each will be in your mind when you have an issue with the paternity of your unborn child. The choice is between invasive testing which could be risky, or non invasive testing which requires a very different fetal DNA sampling method.

First and foremost, the prenatal paternity test must be non-invasive.  Invasive tests such as amniocentesis use needles to puncture the amniotic sac and withdraw a sample of the amniotic fluid, while others take a biopsy sample of a specific part of your placenta known as the chorionic villus (the test is known as chorionic villus sampling).

These can damage the fetus and even cause a miscarriage in up to 1% of cases. Many women refuse an amniocentesis as a routine test for genetic abnormalities, so they are unlikely to accept the procedure just to establish the father of the child.  Why risk the death of your unborn baby to find out who the father is? If there was a 100% safe test would you use that?

Why should you have a prenatal paternity test at all if it has a chance of harming the baby? In fact, if paternity must be established, why not just elect to have a 100% safe test from the outset? Such a test uses the fetal DNA that is contained in the mother’s blood – your blood if you are the mother!

How the Prenatal Paternity Test Works

Your baby secretes DNA continuously into the amniotic sac, the contents of which are continually being renewed and continually passing through your placenta to your bloodstream. From there it is filtered by your kidneys, and then excreted in your urine. By taking a sample of your blood (urine DNA is too diluted to be of use for paternity testing) and a sample of the prospective father’s blood, DNA analysis can establish whether or not the subject is the father.

The laboratory can compare the baby’s DNA with that if the prospective father using large numbers of genetic markers for an accuracy of over 99.9%, the level needed to prove paternity. The reason why our tests offers results that cannot be proved wrong is that we use free DNA strands available in the mothers blood plasma rather than cellular DNA that other testing techniques use.

Cellular DNA is bound into a body cell, and might have originated from an earlier child. Such DNA can remain in your body for many years, unlike serum DNA that remains only for a few hours before it is replaced by more serum DNA from your unborn child.