Percutaneous epididymal sperm aspiration (PESA) and intracytoplasmic sperm injection (ICSI) were carried out in patients with congenital bilateral absence of the vas deferens (CBAVD) and men with failed reversal of vasectomy (FRV). PESA was successful in 55 out of 62 patients with CBAVD (89%) and in 57 out of 60 men with FRV (95%). The fertilization rates after ICSI (53 and 55%), cleavage rates (70 and 76%) and pregnancy rates (36 and 32%) did not differ significantly between the two respective groups (CBAVD and FRV). PESA and ICSI are effective both in patients with CBAVD and in those with FRV.