A modern view of male infertility.

It is archaic to view male factor infertility today separately from in vitro fertilization (IVF) and treatment of the female partner. Oligoasthenozoospermia may be an inherited condition (most likely on the Y chromosome), and is refractory to any treatment of the male including hormones and varicocelectomy. IVF technology is the only justifiable approach for achieving a pregnancy in these couples. The reasons for this view and the suggested modern approach to couples with oligoasthenozoospermia are outlined in this review. However, obstructive azoospermia is different as it can be successfully corrected with microsurgery in over 90% of men. When it cannot be corrected, as in congenital absence of vas, microsurgical sperm retrieval combined with IVF can still be highly effective in producing pregnancy with sperm from the husband. The most important arena for research into male infertility in the next decade will be to map out the deletions on the Y chromosome that might result in defective spermatogenesis, and which probably cause most cases of non-obstructive male factor infertility.