Objectives: The objective of this work was to determine the immune status by researching antitoxoplasmic IgG and IgM. Methods: this is a prospective study from November 4, 2013 to April 4, 2014 carried out at the Exau Kenn medical center laboratory located opposite the Makelekele Base Hospital (I Brazzaville district). A toxoplasmic serology was taken from all pregnant women (first trimester) admitted to the Laboratory as part of a medical follow-up of their pregnancies. Serodiagnosis was performed by the agglutination technique associated with the indirect solid phase immunoenzymatic technique (EIA). Results: Of 139 pregnant women included in our study, 56.12% were immunized and 43.88% unimmunized. The seroprevalence was 69.04%. The percentage of women aged under 20 was 22.22%; and those between 20 and 39 years old was 46.77%; then 31.01% among those over 39 years of age. The risk factors incriminated in toxoplasmic infection for our study were: contact with soil, consumption of raw vegetables, level of hygiene and contact with cats. Conclusion: toxoplasmosis in pregnant women in Brazzaville is a real problem that must be regularly revealed in order to put in place an action plan to identify and evade it.