If you’re pregnant and have questions about the paternity of your growing baby, you may be wondering about your options. Do you have to wait out your entire pregnancy before you can determine the father of your baby?

While a postpartum paternity test is an option, there are also tests that can be conducted while you’re still pregnant.

DNA testing can be completed as early as 9 weeks along. Technological advancements mean there’s little risk to mom or baby. If establishing paternity is something you need to do, here’s what you should know about taking a paternity test during your pregnancy.

Why is it important to take a paternity test during pregnancy?

A paternity test determines a biological relationship between a baby and the father. It’s important for legal, medical, and psychological reasons.

According to the American Pregnancy Association (APA), determining paternity:

  • establishes legal and social benefits such as inheritance and social security
  • provides a medical history for your baby
  • can strengthen the bond between father and child

For these reasons, many states in the United States have laws requiring a form that acknowledges paternity to be completed at the hospital following a baby’s birth.

Once the form is completed, couples have a designated amount of time to request a DNA paternity test for amendments to the form. This form is filed with the Bureau of Vital Statistics as a legally binding document.

Paternity testing: What are my options?

Paternity tests can be performed during or after a pregnancy. Postnatal tests, or those done after a baby is born, can be completed through an umbilical cord collection after delivery. They can also be performed by a cheek swab or blood sample taken at a lab after the baby has left the hospital.

Waiting to establish paternity until delivery, while ensuring accurate results, may be difficult for you and the alleged father. There are several paternity tests that can be conducted during pregnancy.

Noninvasive prenatal paternity (NIPP)

This noninvasive test is the most accurate way to establish paternity during pregnancy. It involves taking a blood sample from the alleged father and the mother to conduct a fetal cell analysis. A genetic profile compares the fetal cells present in the mother’s bloodstream to the alleged father’s. The result is more than 99 percent accurate. The test can also be performed after the 8th week of pregnancy.


Between weeks 14 and 20 of your pregnancy, an amniocentesis test may be performed. Typically, this invasive diagnostic test is used to detect neural tube defects, chromosome abnormalities, and genetic disorders.

Your doctor will use a long, thin needle to take a sample of amniotic fluid from your uterus through your abdomen. The DNA collected will be compared to a DNA sample from the potential father. Results are 99 percent accurate for establishing paternity.
Amniocentesis carries a small risk of miscarriage, which can be caused by premature labor, your water breaking, or infection.

Side effects of this procedure can include:

  • vaginal bleeding
  • cramping
  • the leaking of amniotic fluid
  • irritation around the injection site

You’ll need your doctor’s consent to have an amniocentesis performed solely for the purpose of paternity testing.

Chorionic villus sampling (CVS)

This invasive diagnostic test also uses a thin needle or tube. Your doctor will insert it into your vagina and through the cervix. Using ultrasound as a guide, your doctor will use the needle or tube to collect chorionic villi, small pieces of tissue that are attached to the uterine wall.

This tissue can establish paternity because the chorionic villi and your growing baby have the same genetic makeup. The sample taken through CVS will be compared to DNA collected from the alleged father. There’s a 99 percent accuracy rate.

A CVS can be performed between weeks 10 and 13 of your pregnancy. You’ll need a doctor’s consent when it’s done to establish paternity. Like amniocentesis, it’s typically used to detect chromosome abnormalities and other genetic disorders. Unfortunately, 1 in every 100 CVS procedures will result in miscarriage.

Does date of conception establish paternity?

Some women wonder whether paternity can be established by trying to pinpoint a date of conception. It’s difficult to accurately determine when conception took place because most women ovulate on different days from one month to the next. Plus, sperm can live in the body for three to five days following intercourse.

If you had intercourse with two different partners within 10 days of one another and became pregnant, a paternity test is the only way to accurately determine which man is the father.

How much does paternity testing cost?

Depending on the type of procedure you choose, prices for paternity tests vary between several hundred and several thousand dollars.

Typically, it’s less expensive to test for paternity before the baby is born because you avoid additional doctor and hospital fees. You can inquire about payment plans when you schedule your paternity test.

Bottom line

Don’t trust your paternity test to just any lab. The American Pregnancy Association recommends paternity testing from labs that are accredited by The American Association of Blood Banks (AABB). These laboratories have met stringent standards for test performances.

You can check the AABB website for a list of accredited laboratories. 


Are there any risks to taking an invasive DNA test during pregnancy?


Yes, there are risks associated with invasive DNA testing during pregnancy. The risks include cramping, leaking of amniotic fluid, and vaginal bleeding. More serious risks include small risks of harming the baby and having a miscarriage. Discuss these risks with your physician. 

Alana Biggers, MD, MPHAnswers represent the opinions of our medical experts. All content is strictly informational and should not be considered medical advice.