Parents who have conceived children with the help of sperm or egg donors and then try to find the donors and also other children conceived with the donors' help, often end up creating new forms of extended families, according to research published today (Tuesday 24 February).
The study in Europe's leading reproductive medicine journal Human Reproduction , found that parents set out to find their children's donor and other donor siblings through feelings of curiosity and a desire to enhance their children's sense of identity, and without expecting any very close contact. However, once they had identified the donor and their children's donor siblings, they not only found the experiences of contacting and meeting the donor siblings very positive, but in many cases formed close and continuing bonds.
Dr Tabitha Freeman, a research associate at the Centre for Family Research, University of Cambridge (UK), said: "Our most important finding is that the practice of donor conception is creating new family forms. These family forms are based on genetic links between families with children conceived by the same donor, as well as between donor-conceived children's families and their donors' families. Contrary to what might be expected, this research has found that contact between these new family forms can be a very positive experience for those involved. For example, one very striking finding is that family members in this sample formed close links based on notions of family and kinship; for example the mothers experienced maternal feelings towards their children's donor siblings.
"In addition, it is very interesting that this process is being driven by parents of donor conceived children who, whilst having conceived using anonymously donated sperm, regard it as important for their children to have access to information about their genetic relations."
Dr Freeman and colleagues recruited 791 parents via the Donor Sibling Registry, a US-based international registry that facilitates contact between donor conception families who share the same donor. The parents completed an online questionnaire and data were collected on their reasons for searching for their child's donor siblings and/or the donor, the outcome of these searches and the parents' and children's experiences of any resulting contact.
The parents consisted of 39% lone mothers, 35% lesbian couples and 21% heterosexual couples. In this study, 91% (717) of parents lived in the United States, 5% (37) in Canada and 1% (8) in the UK; other countries of residence included Austria, Germany, Ireland, Spain, Sweden, Australia, New Zealand and Israel. Some parents had discovered large numbers of donor siblings; 11% (55) of parents who had found their child's donor siblings had found 10 or more, with one parent finding as many as 55. An overwhelming majority of parents reported positive experiences of contacting and meeting their child's donor siblings and donor. They frequently described feeling excited and happy on their child's behalf when they found donor siblings, and viewed the addition of such relationships to their children's lives as "enriching", "wonderful" and "fun".
Dr Freeman said the findings have wider implications for research and policy, particularly as an increasing number of countries have removed the right to donor anonymity.
In the paper, the authors write: "The finding that parents placed more importance on tracing and establishing contact with their child's donor siblings than their child's donor has important implications for research and policy in this field. In particular, it is crucial that donor siblings are incorporated into discussions about the regulation of gamete donation, with a key consideration being the number of donor offspring to be conceived using any one donor. The potential for parents and children to form relationships with members of families who share the same donor is a significant consequence of the removal of donor anonymity that has yet to receive adequate attention. This study shows that, while the donor sibling relationship lies at the centre of this phenomenon, a series of wider kinship networks are created, described by those involved as an 'extended family'. These kinship relationships are based on both direct and indirect genetic connections and shared understandings and experiences, out of which new concepts of the family are being defined and negotiated."
Dr Freeman added: "Donor siblings have rarely been mentioned in policy discussions about the regulation of gamete donation, beyond concerns about the possibility of unwitting 'incestual' relationships between people conceived with the same donor.
"A recent example is the proposal made in a report from the British Fertility Society's (BFS) Working Party on Sperm Donation Services in the UK that the maximum number of families created by a single donor should be raised from the current limit of 10. This was proposed as a means of tackling concerns about falling numbers of donors following the removal of donor anonymity. Despite widespread media attention, the potential psychological effects on donor conceived offspring of discovering large numbers of genetic siblings in different families was not considered in this debate.
"Part of the reason that there has been limited discussion of donor siblings is that there has been a lack of research in this area. Whilst this current study provides valuable empirical information, it must be highlighted that further research is required into the experiences of those donor offspring who have found, contacted and met large numbers of donor siblings in order to assess the long-term impact on their psychological well-being."
The study also found differences between types of families had a significant impact on parents' motivations in searching for donor relations. Parents in households without fathers were much more curious about their child's donor and donor siblings.
Dr Freeman said: "Greater differences were found between one- and two-parent families than between father-present (i.e. heterosexual couple families) and father-absent families (lone mother and lesbian couple families). This is important because, in media and policy discussions, lone mothers and lesbian couples are often grouped together and compared to heterosexual-couple families."
She continued: "It is also important to bear in mind that the age and manner in which individuals are told about their donor conception has been found to have a significant impact on how they deal with this information, with those who find out younger in life experiencing more positive outcomes. This may have a knock-on effect in terms of the experience of contacting donor siblings. In this light, it is important to note that the large majority (97%) of the parents in this study had told, or planned to tell, their offspring about their donor conception, with most having done so at an early age."
The study is the first large-scale investigation into the experiences of parents of donor-conceived children searching for and contacting their child's donor relations, and it was conducted by one of the world's leading research groups studying embryo, sperm and egg donation and surrogacy. It is one of three papers in the current issue of Human Reproduction (a journal of the European Society of Human Reproduction and Embryology) that look at parents' attitudes and experiences towards donors .
One of these papers is an editorial commentary by Dr Pim Janssens, an associate editor of Human Reproduction. Writing about Dr Freeman's study, he says: "Overall, these findings suggest that knowledge of donor sibling families is a good thing, and that disclosure of the donor identity makes sense, and need not be a problem. They also suggest that for many parents and children, having only information about donors is not satisfactory - real encounters are the ultimate desire. Unexpectedly these findings might also lead us to question the importance of a common family history for the creation of 'family feeling'. After all, none of the donor families calling their donor sibling relatives shared anything but genes. Nonetheless, many said they felt intuitively bonded."
More information:  Gamete donation: parents' experiences of searching for their child's donor siblings and donor. Human Reproduction, volume 24, issue 3, pages 505-516; doi:10.1093/humrep/den469.
 The other two papers are: "Embryo donation parents' attitudes towards donors: comparison with adoption," (volume 24, issue 3, pages 517-523; doi:10.1093/humrep/den386) by Fiona MacCallum and "Colouring the different phases in gamete and embryo donation," (volume 24, issue 3, pages 502-504;doi:10.1093/humrep/den431) by Pim M.W. Janssens.
Source: European Society for Human Reproduction and Embryology
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