The authors report the cases of a 35-year-old man with a 4-year history of primary infertility with normal clinical examination and semen parameters. Deep genital tract imaging demonstrated isolated unilateral agenesis of the pelvic portion of the left vas deferens associated with abnormalities of the homolateral seminal vesicle. Molecular analysis of the CFTR gene demonstrated composite heterozygosity with the presence of DeltaF508 / V938G mutations. In the light of this case, the authors recommend urogenital imaging for all men consulting for infertility.