Prenatal paternity testing: Establishing the father in the early months of pregnancy

Most paternity tests are carried out any time after the birth of a child up until adulthood or even post-mortem. Sometimes, paternity tests are carried out during pregnancy. In this case, they are referred to as prenatal paternity tests. Prenatal paternity tests are not quite as quick and simple to carry out, mainly because of the method of sample collection required for such a test. Prenatal paternity tests can be divided into invasive and non-invasive tests.

Paternity testing is carried out through a comparison of genetic markers between the alleged father’s DNA profile and that of the child. The problem with carrying out the test in pregnancy is thus clear: how does one get a sample of genetic material from the fetus which is still inside the mother’s womb? There are a number of methods available which enable collecting a sample of fetal DNA including Amniocentesis & Chorionic villus sampling & PUBS (percutaneous umbilical cord sampling), procedures which are often used to determine genetic abnormalities in unborn babies but which carry risks. These procedures are referred to as “invasive” prenatal testing procedures. Due to the risks, pregnant mothers often choose to avoid such tests especially if they need to just determine paternity of the unborn baby.

Non Invasive Prenatal Paternity Testing

Pregnant mothers who need to know the father of the baby whilst still pregnant can avoid all the risks of “invasive” tests by using a much simpler and 100% risk free method known as non-invasive prenatal paternity testing. This test is becoming the preferred way to go about prenatal paternity testing.

The advantages of this test

  • Sample collection is easier than with other prenatal tests such as CVS. A non-invasive test requires just a blood draw from the mother and oral swabs from the father. Click here for more about sample collection.
  • The non-invasive test can be carried out at just 10 weeks of pregnancy, earlier than for example amniocentesis which requires the mother to be at 15 weeks of pregnancy.
  • The most important feature of the non-invasive test is the fact it has 0% risk for the mother and the baby. No type of invasive tests can offer a total guarantee of safety for the mother and the baby.
  • This non-invasive prenatal paternity testing is relatively inexpensive in comparison to invasive techniques such as CVS or amniocentesis.
  • Non-invasive prenatal paternity testing is extremely accurate. If the alleged father is the biological father, the results will confirm a 99.9% probability of paternity

Non invasive prenatal paternity testing will establish the paternity of the fetus. The test cannot be used to discover baby gender. If you want to also find out if you will have a baby boy or baby girl, you will need a baby gender test.

Amniocentesis & Chorionic villus sampling & PUBS

All the above three might ring a bell with mothers. This is because these three methods of fetal DNA sampling are sometimes used to determine whether the baby is developing healthily or not and whether it has some genetic disorder or chromosomal abnormality. These sampling methods are only carried out if earlier preliminary prenatal tests, such as urine analysis and maternal serum testing, indicate a problem.  All three procedures require a qualified OBGYN to be carried out. The time required for each varies but all three procedures need an ultrasound to guide the needle inserted into the correct place. The ultrasound takes around twenty to thirty minutes. All 3 carry the risk of miscarriage. Click here to read more.

The past decade has seen a huge leap in the nature of methods used for prenatal fetal sample collection. It is now possible to extract fetal DNA from maternal blood. This means one can avoid any kind of invasive method that involves entering the womb, stressing the fetus and the possibility of miscarriage. Starting at the tenth week of pregnancy, when levels of fetal DNA in the maternal blood supply are high enough, it becomes possible to separate the fetal DNA in the maternal blood sample from the maternal blood itself. Once the fetal DNA fragments have been separated, specific genetic sequences are analyzed and compared to those of the alleged father to confirm or exclude a match. The non invasive prenatal test for paternity provides a 99.9% accurate result.

Fetal genetic sampling from maternal blood is a zero risk test and does not require an ultrasounds or OBGYN. Currently, intensive studies are underway to use this method to know whether or not the child suffers from a genetic disorder or chromosomal abnormality such as Down’s syndrome, a condition characterized by the presence of one extra chromosome.  Studies are indeed very promising and many leading universities and laboratories have published their findings. In future, amniocentesis and CVS will likely not be used any longer, which signifies healthier and safer pregnancies.