

Has your doctor asked you to undergo a Toxoplasma IgG / IgM test?These tests play a key role in detecting toxoplasmosis, a parasitic infection that often shows no symptoms but can be dangerous in certain situations—especially during pregnancy or in people with weakened immune systems.In this comprehensive guide from Dalili Medical, we’ll walk you through everything you need to know about the Toxoplasma IgG and IgM tests:
What they mean
When they are recommended
The difference between IgG and IgM antibodies
How to interpret the results—especially in pregnant women and newborns.
Toxoplasma gondii is a parasite that can infect humans through:
Eating undercooked or raw meat
Contact with infected cat feces
Contaminated soil or unwashed vegetables
Mother-to-child transmission during pregnancy
While most people experience no symptoms, the infection can cause serious complications in:
Pregnant women (risk to the fetus)
Immunocompromised patients (e.g., HIV, cancer)
Newborns (if infected in the womb)
This blood test detects antibodies your immune system produces in response to the parasite:
IgM: Indicates a recent or active infection
IgG: Indicates a past infection and possible immunity
Doctors may recommend it if you:
Are pregnant, especially during the first trimester
Have symptoms such as swollen lymph nodes or unexplained fever
Experienced recurrent miscarriages or fetal abnormalities
Have a weakened immune system
Have a newborn with suspected congenital infection
IgG Result | IgM Result | Interpretation |
---|---|---|
Negative | Negative | No current or past infection – take preventive measures |
Positive | Negative | Past infection – immunity likely, no active infection |
Negative | Positive | Possible recent infection – needs further testing |
Positive | Positive | Active or recent infection – confirm with additional tests |
IgG & IgM Negative: No infection; important to follow preventive practices
IgG Positive, IgM Negative: Past infection, immune system has protection
IgM Positive: May indicate recent infection; confirm with IgG Avidity Test:
Low avidity: Recent infection → higher risk to fetus
High avidity: Older infection → low risk to fetus
In healthy individuals:
Mild flu-like symptoms
Swollen lymph nodes
Fatigue
In pregnancy:
Often no symptoms in the mother
Risks to the fetus: brain damage, vision issues, miscarriage
In immunocompromised patients:
Encephalitis (brain inflammation)
Eye complications
Life-threatening conditions
Especially important for pregnant women:
Cook meat thoroughly (no pink color)
Wash vegetables and fruits well
Avoid handling cat litter or wear gloves
Use gloves while gardening
Drink only clean, safe water
No. Fasting is not required for Toxoplasma IgG / IgM testing.
Yes. False-positive IgM results may occur. That’s why doctors often order:
IgG Avidity Test – to confirm the timing of infection
PCR Test – especially useful for testing amniotic fluid in pregnancy
Is toxoplasmosis always dangerous?
No. It's usually mild in healthy people but serious in pregnancy or weakened immunity.
How common is toxoplasmosis?
Very common. Many people have had it without knowing and developed lifelong immunity.
Can toxoplasmosis be treated?
Yes. Active infections, especially during pregnancy, can be treated with medications like Spiramycin, Pyrimethamine, and Sulfadiazine under medical supervision.
Are these tests available everywhere?
IgG and IgM tests are widely available. Advanced tests like Avidity or PCR are often done in specialized labs.
The Toxoplasma IgG / IgM test is an essential tool for diagnosing toxoplasmosis—especially during pregnancy or in people at higher risk. Accurate interpretation of results helps prevent complications and guides proper treatment.
If your doctor recommends this test, don’t panic. Early detection is key to protecting your health and the health of your baby.