Gestational and Congenital Toxoplasmosis: An Updated Review with Emphasis on High-Prevalence Countries

Toxoplasmosis remains one of the most common parasitic infections affecting humans, with significant implications for pregnancy and fetal health. Maternal primary infection during gestation can result in transplacental transmission of Toxoplasma gondii, leading to a wide spectrum of congenital disease. The risk of vertical transmission increases with gestational age, whereas disease severity is inversely related—early infections causing severe neurological and ocular damage, and late infections often resulting in subclinical forms. Advances in serological testing, including IgG avidity assays and molecular diagnostics such as PCR on amniotic fluid, have improved early detection and management. Prenatal treatment with spiramycin or pyrimethamine–sulfadiazine–folinic acid combinations has been associated with reduced transmission and less severe fetal disease in several studies, although the magnitude of benefit remains debated. Long-term follow-up is essential, as late-onset manifestations, particularly chorioretinitis and neurodevelopmental impairment, are common. This narrative review was based on a comprehensive literature search of major medical databases and summarizes current knowledge on the epidemiology, pathophysiology, diagnosis, treatment, and outcomes of toxoplasmosis in pregnancy. Particular emphasis is placed on high-prevalence countries, where greater parasite genetic diversity, distinct epidemiological patterns, and a higher burden of congenital disease pose unique clinical and public health challenges. Despite progress in understanding parasite biology, pathogenesis, and treatment efficacy, congenital toxoplasmosis continues to be underdiagnosed and underreported, especially in low-resource settings. Ongoing challenges include optimizing screening strategies, ensuring access to standardized therapies, and strengthening surveillance systems.