Paternity testing can be done between 8 and 18 weeks of pregnancy.
There are two main types of paternity testing during pregnancy, the first being the collection of fetal chorionic villus or amniotic fluid for testing, and the second being the extraction of peripheral blood from the pregnant woman for testing. The first method is surgical sampling, which is relatively risky. Usually, when collecting fetal villus for testing, the pregnant woman needs to be 8-13 weeks pregnant; when collecting amniotic fluid for testing, the pregnant woman needs to be 14-28 weeks pregnant.
Peripheral blood sampling is non-invasive and relatively safe. The DNA of the fetus can be extracted from the peripheral blood of the pregnant woman and compared with the DNA of the male partner to determine whether the fetus is related to the male partner.
There are some differences in the accuracy of the two methods of paternity testing during pregnancy, with amniotic fluid testing being 99.99% accurate and peripheral blood testing being 99% accurate.
When testing for paternity during pregnancy, you should choose a regular medical institution and select a suitable method of identification under the guidance of a physician according to the physical condition of the pregnant woman.