The serological prevalence of Toxoplasma gondii was studied among 839 pregnant women in two hospitals from Franceville (Gabon), between May 2007 and December 2007. Specific T gondii IgG and IgM were measured by Enzyme Linked Fluorescent Assay (ELFA). Datation of the infection was carried out by avidity test. Fifty-six percent of women in this study were immunised compare to the 71% who were found as immunised in a previous study carried out fifteen years ago. 2.6% were found to be IgM positive. However, from the avidity test it was found that these infections occurred before pregnancy contact with cats and age increase this prevalence. The lack of information for pregnant women, the lack of continuous training for health personnel and lack of awareness about interpretation of laboratory diagnostic tests like avidity test in these hospitals reduce the level of counselling for women about T gondii.