It is estimated that of the 50–80 million couples who are infertile worldwide, there is a significant male component in about one-third. The only effective therapy for these couples has been the use of reproductive technology and, with the development of microinjection any man who has got some sperm can potentially be treated (see Chapter 10). Unfortunately many couples who attempt reproductive technology will not become pregnant. Other couples do not have the financial resources to enter these programmes, and some others are morally opposed to the techniques involved. Furthermore, there are men who have got no sperm at all and these couples are candidates for donor insemination.

The use of donor sperm to produce a pregnancy for couples where the male is infertile has been practised for many centuries. It can be carried out without medical intervention if a donor known to the couple donates sperm and the couple self-inseminate. The disadvantage of this method is that there is only minimal screening and there is a risk of transmitting sexually transmitted diseases.

The next level of sophistication came when the donors were recruited by medical practitioners and the semen was used ‘fresh’ to inseminate the wife of the infertile male. The problems of using fresh semen are again that matching is limited, screening is not possible and there is a risk of transmitting infectious agents. In the 1990s only sperm that has been frozen, screened and quarantined should be used.