Purchase your DNA test and any additional test options here.
If you are purchasing a DNA test for immigration purposes or a purchasing a forensic test, please contact us first.

If you have any questions, or if you'd like to discuss your personal case, please contact us on 02 381 5410, 086 347 7620, or thailand@ptclabs.com.

Invasive Prenatal Paternity Test (Amnio)

Invasive Prenatal Paternity Test (Amnio)

Price: THB 25,900



A Prenatal Paternity Test using amniotic fluid samples requires the Mother to undergo a common antenatal procedure, called amniocentesis. This invasive procedure is performed by an OBGYN to extract amniotic fluid from the Mother, which contains Fetal DNA. With this, plus a mouth swab from the Mother and the Alleged Father, we can conclusively determine paternity. 

Once you have your amnio sample, we use a microcentrifuge to spin and separate the unborn Child's Fetal DNA from the amniotic fluid, and this is what is tested against the DNA from mouth swabs of the Mother and the Alleged Father. STR analysis is used to determine the paternity of the unborn Child.

Paternity Testing Corporation will continue testing your samples until we reach a minimum Paternity Index (PI) of 10,000, or 99.99% for both Peace-of-Mind (At-Home) Tests and Legal (Chain-of-Custody) Tests. This guarantee applies whether the Mother is included or not, in the event of poor samples such as too much blood contamination in the supplied amniotic fluid (we may request a new sample), or if we find mutations in the Child’s DNA. These would all require either further STR analysis by testing more loci, or by switching methods to RFLP testing; all of which we would do at no additional charge to you, in order to reach our 99.99% probability guarantee.

Whether you need a Peace-of-Mind (At-Home) Test, or a Legal (Chain-of-Custody) Test, the actual lab testing and analysis is identical, with the same level of rigorous testing methods and the same 99.99% probability guarantee. Just because you are getting a ‘home’ test, does not mean you do not deserve proper testing and a correct, conclusive answer. The only difference for a legal test is in how your samples are collected (see below).

The price includes:

  •  24/7 personal customer support in English and Thai.
  • DNA Sample Collection Kit, containing everything you or your sample collector needs to collect samples and complete paperwork. Note that the cost of the amniocentesis procedure is not included in the test fee, as it is not a service provided by PTC. We can, however, recommend reputable OBGYNs to perform the procedure.
  • The Chain-of-Custody (CoC) Fee (for Legal Tests) is waived for this test. Please see below for extra information regarding Legal Tests and chain-of-custody of samples.
  • Preparation of the amniotic fluid for transportation to our laboratory.
  • One (1) shipment of your samples (up to 0.5 kg in one shipment) by first-class, international priority courier to our lab in the USA.
  • Testing of DNA samples provided on cotton tip for one (1) Alleged Father, and one (1) Mother, plus the DNA of one (1) Fetus (via amniotic fluid). To test additional people, you will need to add this option to your order. Scroll down the page to add this option to your order. To use unusual samples in this test (for Alleged Father only), you will need to add this option to your order. Scroll down the page to add this option to your order.
  • One (1) original, notarized English-language report, and one (1) original, notarized Thai-language report.
  • Emailed results as soon as they are ready.
  • Posting of hard-copy, notarized results to anywhere in the world by regular mail. To express the postage of your hard-copy results, you can upgrade to first-class, international priority courier. Scroll down the page to add this option to your order.


For our Invasive Prenatal Paternity Tests (Amnio), we waive the Chain-of-Custody (CoC) Fee (usually THB 1,500). Tests required for legal or official purposes must follow a strict chain-of-custody of the samples, including the amniotic fluid and samples from Mother and Alleged Father. Learn more about chain-of-custody of samples in our FAQ.

Chain-of-custody means your DNA samples were collected by a certified, independent third party, and that your identity has been verified and documented. Following this process means your result report will be recognized as an official, legal document. Learn more about legal testing and chain-of-custody of samples

If you require a PTC representative to visit you at the hospital after your amniocentesis procedure, a Visit Service fee will apply (scroll down the page to add this option to your order). In some cases, however, this fee can be waived. Contact us for details.

Important Information


  • An Invasive Prenatal Paternity DNA Test (Amnio) can be used for peace-of-mind (there is no chain-of-custody of samples, meaning you bring the amniotic fluid to our office on your own and you collect your own samples from Mother and Alleged Father), or for legal, official purposes (your samples must follow a strict chain-of-custody procedure, meaning the DNA is collected by a certified, independent third party, and your identity has been verified and documented). Learn more about the difference between legal testing and peace-of-mind testing in our FAQ. 
  • If you plan to use your results for any legal or official purpose in Thailand or Taiwan, there is an Authentication Process that must be followed, and we can take case of the whole process both in the USA and in Thailand. Scroll down the page to add this option to your order.
  • Our results are accepted in many countries around the world for Immigration and other official purposes. If you are using your results for Immigration purposes, please read our section on Immigration DNA Testing, and contact us for more information about your specific Embassy, as some Embassies require you to first make an application with them, before doing a DNA Test.


While this kind of prenatal paternity test can be performed at 12 weeks of pregnancy, the majority of OBGYNs will only perform the prerequisite amniocentesis procedure after 16 weeks of pregnancy (maximum 30 weeks), for the sake of both Mother and Fetus. Read below for more information on amniocentesis.


The DNA test itself does not pose any risk at all to the unborn Baby or the Mother, however the amniocentesis procedure is an invasive one. This means that the amniotic fluid is extracted using an ultrasound-guided needle, inserting it into the amniotic sac surrounding the Fetus. Amniocentesis is usually performed in conjunction with other genetic testing, such as chromosome screening for genetic abnormalities. Amniocentesis is a common procedure, carried out daily by qualified OBGYNs. There is, however, a 0.05% risk of miscarriage from the amniocentesis procedure. For this reason, most OBGYNs will only perform the amniocentesis procedure after 16 weeks of pregnancy, and at a maximum of 30 weeks' pregnant, for the sake of both Mother and Fetus.


  • Testing times can vary depending on the samples provided. Generally, for tests with good oral samples from Mother and Father, and clear amniotic fluid samples with no-to-minimal blood contamination, it will take approx. 7-10 business days. Tests using unusual samples for Alleged Father/s will take longer. This includes both the time it takes to send your samples to our lab in the USA (2 business days) by first-class, international priority courier, and also the testing time at our lab. 
  • We provide a guarantee based on our 99.99% probability of paternity. This means that we will continue testing until we reach this probability, at no extra cost to you. This can also mean that our usual 5-8 day window of testing can take longer if, for example, the Mother's oral sample is not included in the test, there are mutations in the DNA from one tested generation to the next, the samples contain a high bacteria count, or other reasons that are out of our control. 
  • This is why we do not guarantee how long it will take to deliver results, but we guarantee the accuracy of our results.
  • If you are in a hurry, we have an express testing option. Note that if we cannot get a minimum of 99.99% probability within the express timeframe, you will be refunded for the express fee. Scroll down the page to add this option to your order.
  • Your results will be sent to you immediately by email. Your physical results will be sent to your via regular post and will arrive in Thailand approximately 2 weeks after you receive your emailed results. 
  • If you’re in a hurry, you can also opt to have your results sent via first-class, international priority courier for an additional fee, and your results will arrive within approximately 2 business days. Scroll down the page to add this option to your order.


In the event of a negative test, the report you will receive will show 0% probability of paternity, which conclusively excludes the man tested as being the Father of the Child. In the event of a positive test, the report you will receive will show 99.99% not excluding the tested man as being the Child’s Father. This guaranteed probability is above industry standards, and we will not issue a result that does not match this conclusive level of probability. 


  • For the unborn Child (Fetus), we require at least 6cc of amniotic fluid. The Mother must first undergo an amniocentesis procedure with an OBGYN qualified to collect this sample of amniotic fluid. The cost of the amniocentesis is not part of the test fee, and you will pay the OBGYN directly for the procedure. We can recommend reputable QBGYNs or you can suggest your own. Contact us for the DNA Sample Collection Kit.
  • For Mother and Alleged Father, samples are usually collected using buccal swabs (sterile Q-Tip/cotton tip) - which are provided in our DNA Sample Collection Kits - by swabbing the inside of the cheek. If you are collecting your own samples for a Peace-of-Mind (PoM) Test, you can view our sample collection guidelines here.
  • If normal samples are not possible to obtain for the Alleged Father, you can view our Unusual Samples page to see what other types of samples can be used for this test. Most unusual samples will incur a fee, as we must first extract the DNA in order to analyze it. Contact us for more information.


No, you must test any Alleged Father that may be related to each other. If there is more than one possible Father of the Child and the possible Fathers are closely related to each other (i.e. as brothers, or as father and son, etc.), then it is very important to test them both due to the similarities in their DNA, in order to avoid a false-positive result; a positive result for one relation will not exclude the other, unless both/all are tested. The same applies to related Alleged Mothers in a Maternity DNA Test. Learn more about DNA testing related Alleged Fathers/Mothers in our FAQ.


Legal Sample Collection by PTC

THB 1,500

Visit Service (<15 km)

THB 500

Express Testing

THB 4,800

Visit Service (15-35 km)

THB 1,000

Express Authentication (per Case)

THB 6,600

Express Delivery (Courier)

THB 2,700

Visit Service (35-100 km)

THB 2,000

Unusual Sample (per Sample)

THB 8,300

Additional Person

THB 7,500

Visit Service (100-200 km)

THB 3,000