For infertile patients with azospermia ,donor sperms can be used with their consent. The samples are taken from sperm banks. The donors undergo various tests like HIV, VDRL, Australia Antigen to prevent risk of infection. The samples are frozen for 6 months after which the donors undergo the tests once more. If they are negative then their frozen samples are used to achieve pregnancy. Matching donor samples can be selected with respect to height, complexion, hair colour etc. and complete confidentiality is maintained.