The Toxoplasma gondii test is used to detect an active infection in a pregnant woman, unborn baby, or individuals with a weakened immune system (immunocompromised), particularly when flu-like symptoms are present. It can also help determine if someone has had a previous Toxoplasma infection or assist in identifying whether certain complications are due to an active infection. This test is crucial in managing risks associated with Toxoplasmosis, especially during pregnancy and in vulnerable populations.