Azoospermia and paternal autosomal ring chromosomes: case report and literature review.

Two men of the same family presented with ring chromosome 22 and azoospermia. The literature on all autosomal ring chromosomes and semen abnormalities was reviewed. Autosomal ring chromosomes were often associated with a low sperm count. This is probably as a result of gamete instability at meiosis due to the ring chromosome which leads to an increased breakdown. In addition, ring chromosomes transmitted from the parents may manifest quite differently in the progeny. Prior to treating these patients with assisted reproduction, appropriate counselling should be offered, in view of the varying phenotypic manifestations of ring chromosomes in the resulting progeny, and prenatal diagnosis or preimplantation diagnosis must be considered.