Skip to content

Health & Pregnancy

Font Size

Toxoplasmosis Test for Fetus - Topic Overview

When a pregnant woman has toxoplasmosis, a PCR test on amniotic fluid is used to learn whether her fetus is also infected.

Polymerase chain reaction (PCR) is a method of duplicating DNA strands from a tiny sample of blood, hair, or tissue. PCR is used to identify infectious diseases, genetic conditions, and genetic links between people.

PCR is preferred over a fetal blood test for antibodies because:1

  • Collecting amniotic fluid through amniocentesis is considered safer than fetal blood sampling.
  • PCR is better than antibody testing to detect toxoplasmosis.
  • PCR can be done earlier in a pregnancy than a blood test for antibodies. Because first- and second-trimester fetal infection carry the highest risk of birth defects and intellectual disability, earlier test results are important to parents who are considering ending such a pregnancy.

In rare cases, PCR produces false-positive or false-negative test results. Follow-up testing and fetal ultrasound monitoring for hydrocephalus can help confirm PCR test results.

PCR is seldom used to diagnose toxoplasmosis in adults. Antibody testing of a blood sample is easier and more widely available.

    WebMD Medical Reference from Healthwise

    Last Updated: May 29, 2013
    This information is not intended to replace the advice of a doctor. Healthwise disclaims any liability for the decisions you make based on this information.
    1
    Next Article:

    Toxoplasmosis Test for Fetus Topics

    Pregnancy Week-By-Week Newsletter

    Delivered right to your inbox, get pictures and facts on
    what to expect each week of your pregnancy.

    Today on WebMD

    hand circling date on calendar
    Track your most fertile days.
    woman looking at ultrasound
    Week-by-week pregnancy guide.
     
    Pretty pregnant woman timing contaction pains
    The signs to watch out for.
    pregnant woman in hospital
    Are there ways to do it naturally?
     
    slideshow fetal development
    Slideshow
    pregnancy first trimester warning signs
    Article
     
    What Causes Bipolar
    Video
    Woman trying on dress in store
    Slideshow
     
    pregnant woman
    Article
    Close up on eyes of baby breastfeeding
    Video
     
    healthtool pregnancy calendar
    Tool
    eddleman prepare your body pregnancy
    Video