In which pregnancy stage is the risk of fetal infection from toxoplasmosis highest?

The risk of fetal infection from toxoplasmosis is highest during the first trimester. This is because during early pregnancy, the fetal immune system is not fully developed, making the fetus more vulnerable to infections. If a mother becomes infected with Toxoplasma gondii during this critical period, the parasite has a greater likelihood of crossing the placenta and causing complications such as miscarriage, stillbirth, or congenital toxoplasmosis, which can lead to serious health issues for the newborn.

While the risk of transmission increases later in pregnancy, the consequences of infection are generally more severe if the mother becomes infected during the first trimester, as the developing organs are at their most crucial stages. Therefore, understanding the timing of maternal infection is key in managing the health risks associated with toxoplasmosis during pregnancy.