How Soon Can You Get a Paternity Test During Pregnancy?

Non-invasive prenatal paternity testing can be performed as early as week 8 of pregnancy using a maternal blood draw and a cheek swab.

You probably assumed paternity testing during pregnancy meant waiting until the second trimester — or that it required a needle inserted into your abdomen. Neither is true for the most common option available today.

Non-invasive prenatal paternity (NIPP) testing uses a simple blood draw from the pregnant person and a DNA sample from the potential father. It can be done as early as the eighth week, with no risk to the pregnancy. Here is what you need to know about timing, accuracy, and which test fits your situation.

How Early Can You Test

The timing depends on which type of test you choose. The most common option — non-invasive prenatal paternity testing — analyzes cell-free fetal DNA circulating in your blood. Enough of this fetal DNA is present to allow accurate analysis starting around the seventh or eighth week of pregnancy.

Cleveland Clinic states that a healthcare provider can perform NIPP testing as early as the 8th week of pregnancy. Some sources, including the American Pregnancy Association, suggest it can be done as early as week 7. The variation depends on the lab’s protocol and the fetal DNA concentration in your blood.

Your provider may order an ultrasound to confirm gestational age before the blood draw. This ensures enough fetal DNA is circulating for a reliable result. A quick ultrasound adds no risk and can prevent the need for a repeat draw.

Why The Timing Question Matters

You might be anxious for an answer earlier than the standard NIPT screening timeline. Non-invasive prenatal testing (NIPT) for chromosomal conditions is typically done after week 10. Paternity testing can be scheduled much sooner, which matters if you need information for personal, legal, or medical reasons.

Here is how the main prenatal paternity options compare:

• Non-invasive prenatal paternity (NIPP): A blood draw from the pregnant person plus a cheek swab from the alleged father. Available from week 7-8 onward. No risk of miscarriage. Results typically in 3-7 days.
• Chorionic villus sampling (CVS): An invasive procedure that samples placental tissue. Can be performed between weeks 10 and 13. Carries a small miscarriage risk. Usually reserved for genetic diagnostic purposes, not paternity alone.
• Amniocentesis: An invasive procedure that samples amniotic fluid. Performed between weeks 15 and 20. Carries a small miscarriage risk. Can also detect neural tube defects and fetal lung maturity.
• Postnatal test: A cheek swab after the baby is born. No restrictions on timing, no risk, and the same high accuracy. Requires waiting until delivery.

Most people choose NIPP testing because it avoids the miscarriage risk associated with invasive procedures. If you only need a legal document, some courts require a postnatal test for admissibility, so check your specific situation before ordering.

Accuracy and Safety of Prenatal Paternity Testing

Non-invasive prenatal paternity tests are highly accurate — Cleveland Clinic notes results often exceed 99.9% accuracy when the alleged father provides a sample. That level of reliability is comparable to a standard paternity test performed after birth.

The test works by isolating fetal DNA fragments that naturally cross the placenta into your bloodstream. A lab compares specific genetic markers from the fetal DNA to markers from the alleged father’s cheek swab. If the markers match across enough locations, the probability of paternity is calculated.

Because NIPP testing only involves a routine blood draw, it carries no risk of miscarriage. Invasive prenatal paternity tests — CVS and amniocentesis — carry a small but real risk of pregnancy loss, which is why they are rarely used solely for paternity determination. For most people, the non-invasive prenatal paternity test is the safer and simpler choice.

Note that NIPT screens for conditions like Down syndrome, not paternity. If you need both, you can discuss with your provider whether doing NIPP testing earlier and NIPT later makes sense for your situation.

What You Need Before Ordering

Before you can schedule a prenatal paternity test, you need a few things in place. Here is the typical process:

1. A healthcare provider to order it: Your OB-GYN, midwife, or a general practitioner can order the blood draw. Some direct-to-consumer companies also offer NIPP testing with a provider referral.
2. A DNA sample from the alleged father: The test requires a cheek swab or blood sample from the potential father. If he is not available, some labs offer discreet mailed swab kits, but legal paternity cases may require witnessed collection.
3. Ultrasound confirmation of gestational age: Most providers want to confirm you are at least 7-8 weeks along before drawing blood. This prevents a failed test from low fetal DNA concentration.
4. Consent from both parties: Ethical and legal guidelines generally require informed consent from both the pregnant person and the alleged father. Some states have additional requirements for legal admissibility.

The alleged father does not need to be present at your appointment in many cases. Labs can mail him a swab kit, or he can visit a separate collection site. Check with the specific testing company about their collection options.

Cost, Turnaround, and What to Expect

Prenatal paternity testing is not typically covered by insurance, since it is not a medical necessity. Costs vary widely but generally range from roughly $500 to $2,000 depending on the lab, whether rush processing is selected, and whether legal documentation is required.

Results usually arrive within 3 to 7 business days after the lab receives both samples. Some companies offer 48-hour processing for an additional fee. If you need results for legal purposes, ensure the lab follows chain-of-custody procedures — this typically adds time and cost but makes the result admissible in court.

Per Healthline’s guide on comparable to postnatal test accuracy, prenatal non-invasive tests match the reliability of tests done after birth. That means you can trust the result with the same confidence you would have if you waited until your baby arrived.

If the alleged father is unavailable or refuses to provide a sample, non-invasive prenatal paternity testing cannot be performed. In those rare cases, the only option is to wait until after delivery and pursue a court-ordered test.

The Bottom Line

You can get a paternity test as early as the seventh or eighth week of pregnancy through a non-invasive blood draw and cheek swab, with accuracy above 99.9% and zero risk to the pregnancy. Invasive options like CVS and amniocentesis are rarely used for paternity alone because they carry a small risk of miscarriage.

Your OB-GYN or midwife can confirm your gestational age with an ultrasound and help you arrange the NIPP test through a reputable lab — just ask at your next appointment whether your specific week count is sufficient for the draw.