Currently, the Human Fertilisation and Embryology Authority (HFEA) limits the use of gametes from a single donor to a maximum of 10 families, although it notes that this is an arbitrary figure (4). A majority of the BFS Working Party supported raising this to 20 families, while a minority advocated an increase to 15 and some suggested no change (we understand that those outside the majority group included representatives of counsellors and donor-conceived families, though this significant fact was not reported). In the absence of any consensus, either domestically or internationally, on the principles underlying donor limits (5) the suggestion of raising them warrants further discussion.
Current donor limits in the UK, as in many other jurisdictions, were established within the context of donor anonymity. The risk of 'unwitting incest' between genetic relatives was considered of greater concern than the challenges faced by the donor-conceived in '[coming] to grips with multiple genetically-linked siblings in a number of different families' (6). Among jurisdictions that enable the donor-conceived to learn the identity of their donor Sweden sets the donor limit at six children, Switzerland eight, New Zealand ten and the Netherlands 25. Where the criterion is the number of families Austria restricts donations to three marriages (or couples in a de-facto marriage) and Finland to five recipients. Proposed legislation in New South Wales, Australia also imposes a five-recipient limit that includes the marital relationships (but not the non-marital liaisons) of the donor which resulted in the birth of a child. The limit in Western Australia is five families. Like the UK, Victoria has a limit of ten families, although proposed legislation would include in this number families with children by the donor's current or former partner. Norway combines both criteria, with limits of six or seven families and 12-14 children.
The context within which most proposals to increase donor limits arise is that of 'supply and demand'; where the two do not balance, either input or output requires attention. We approach the issue from an alternative perspective which focuses on the well-being of the families built as a result of donor conception and, in particular, the individuals whose entire lives are affected as a consequence of being donor-conceived. From this perspective, questions of supply and demand are the wrong questions to ask.Indeed, we need to remember that we are still at the stage of asking questions rather than providing answers. Both the BFS (1) and the HFEA (4) acknowledge the paucity of good-quality social science research relevant to this field. Anecdotally, we hear that (at least some) donors in the UK already place lower limits on the maximum number of families that may include their genetic offspring. However, this information is not routinely collected, much less analysed in an attempt to understand donors' perspectives on the children they are a party to conceiving and the families they help to build. Similarly, little is known about the views of those who have the most at stake, donor-conceived people themselves. We are aware of a single research study that has highlighted the concerns of the donor-conceived about having potentially large numbers of genetic relatives. According to the report, some participants were 'deeply disturbed by the thought of almost a tribe of offspring from their provider' (7). Considering the risk of consanguinity solely in terms of probability - and then rejecting it, like the BFS (1) and the HFEA (4), as extremely unlikely - fails to consider the impact of the fears of donors (in relation to their own children), the donor-conceived and their parents of discovering that a former or existing sexual partner was in fact a half-sibling or biological parent (8, 9).
Until we have relevant, good-quality empirical evidence that can inform the direction of future policies, donor limits should be left alone.