Exams and Tests
In
most areas of the United States and Canada, fetal
toxoplasmosis infection is rare. In the United States,
about 1 to 10 infants per 10,000 actually become infected before birth.1 This is why screening for toxoplasmosis is not a part of
routine prenatal care in this country. But getting tested for toxoplasmosis may
be a good idea if you are pregnant or planning to become pregnant and:
- You are worried that you might get
toxoplasmosis.
- You think you may not be able to avoid exposure to
the parasite.
Consider what higher-risk countries recommend as you make
your decision about testing:
A blood test is used to see whether you have the
antibody to the toxoplasma parasite. If you have the
antibody, that means you have already been infected, and your
immune system now makes antibodies that can fight
toxoplasma. These antibodies protect your fetus and newborn from
infection.
You may need more than one blood test to make sure the
result is accurate.
Tests for toxoplasmosis
- Toxoplasmosis blood
test looks for the antibody to toxoplasma. If test results or symptoms
show possible infection, another test is done 2 to 3 weeks later to confirm the
diagnosis.
- Amniocentesis is used to collect amniotic fluid for
testing. A
polymerase chain reaction (PCR) test is used on the
fluid to check for signs of toxoplasma
DNA. This test can detect fetal toxoplasmosis.
- Fetal ultrasound is used to check for signs of
toxoplasmosis damage in the fetus.
Early Detection
Birth defects are most likely to
develop when a fetus is infected during weeks 10 through 24 of
pregnancy.4 This is why early detection and treatment
of fetal toxoplasmosis is important for preventing severe fetal problems. (If
an infection develops later in pregnancy, severe fetal problems are less
likely, but treatment is important to prevent future problems.)