When spermatozoa are not found in the ejeculate or even in the testicular biopsy of a man, an alternative for a couple to achieve a pregnancy is to use donated sperm.

A compatible donor is found and his spermatozoa can be introduced into the woman´s uterus at the time of ovulation using a catheter ( artificial insemination using donor sperm).
The donor is extensively screened for hereditary and infection factors before it is accepted into the donor program.
It can be used also, in cases where a man carries a hereditary disease he does not want to pass on to his offspring. Single women who want to become mothers can use this method.