Анотация: Almost all the fertility parameters in sows (reproductive and productive) may be affected by different infectious diseases. Changes in reproductive parameters may also occur without the appearance of appreciable pathological findings or with clinical signs often overlapping or similar to different diseases or pathogens. All the clinical aspects and the pathological findings should be taken into account to address a tentative diagnosis with the support of laboratory findings. All the pathologic material available in the course of reproductive problems in sows should be taken into account for laboratory investigations, including examination of reproductive and urinary tract of reformed sows from the abattoir. Laboratory investigations include pathogen identification or isolation, antibody titer evaluations, chemical investigations of toxins with activity on the reproductive tract and tissue histology. For the control of reproductive diseases in sows, antibiotic therapy, prophylaxis and immunization programs should be taken into account