The donation of eggs or sperm by a family member is known as inter-family donation. It provides a genetic link between the recipient and the child (unlike conception with arms-length donated eggs or sperm), which can be an important driving factor in some cases. To prevent consanguinity (incest), there are legal restrictions as to the mixing of eggs and sperm between close relatives. However, inter-family donation is permissible in some cases at UK fertility clinics.