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How Prenatal Testing Works

Pregnancy Involves Many Tests

Throughout the course of a pregnancy, an expecting mother will have many tests. They fall into the following categories:

  • pregnancy test - the first test
  • routine, non-invasive tests - these occur during each visit to the obstetrician's office: blood pressure, urine glucose/protein, fetal heartbeat
  • blood sampling tests - usually done once at various times during pregnancy: blood type, Rh Factor, determine iron levels, HIV, Hepatitis B, syphilis, glucose tolerance test, triple screen test
  • swab tests - usually done once at various times during pregnancy: Pap smear - to check for STDs, various bacteria (varies according to the laws of each state); Group B streptococcus screening
  • ultrasound - done at least one time during pregnancy
  • tests done under special circumstances: amniocentesis, chorionic villus sampling, fetal blood sampling or percutaneous umbilical blood sampling, fetal monitoring

Let's look at the various tests to see how they work and what they can tell us about the developing baby.