'I have to remind myself that everyone's search is different': experiences and outcomes of searching and not searching for donor connections among donor conceived adults.

study questionWhat are the experiences and outcomes of donor conceived adults who are actively searching for, open to contact with, or not searching for donor connections? SUMMARY ANSWER: Most participants were actively searching or open to contact, and 67% had found or been found by a connection; finding or not finding experiences were complex. WHAT IS KNOWN ALREADY: There is variation among donor conceived individuals in their interest in donor connections. Individual reasons for searching for connections, and which donor connections are searched for, also vary. Most research studies have focussed on individuals who are actively searching for their donor or donor siblings. Global increases in direct-to-consumer DNA testing and social media participation mean that connections may be made to individuals unaware of their (or their relatives') involvement with donor conception. These social and technological changes have also increased the chances of donor conceived individuals being contacted without expecting or desiring contact. STUDY DESIGN, SIZE, DURATION: This study included 88 donor conceived adults, in the UK, who participated in an online multi-method survey between January and August 2022. The survey was designed in consultation with staff and volunteers from the UK's largest community networks for donor conception families (Donor Conception Network, DCN) and donor conceived people (Donor Conceived Register Registrants' Panel, DCRRP). It was piloted by five donor conceived people before its launch. Participants were recruited with assistance from DCN and DCRRP, via social media, university mailing lists, and snowballing. PARTICIPANTS/MATERIALS, SETTING,

methodsParticipants were mostly female (n = 65, 74%) and sperm donor conceived (n = 79, 90%). Of the 88 participants, 39 (44%) were actively searching for their donor connections, 44 (50%) were open to contact but not actively searching, and 5 (6%) were not searching. Questions were closed (yes/no, rating scale, or multiple choice) or open-ended, addressing experiences of donor conception, searching for connections, and finding or not finding connections. Data were analysed both quantitatively and qualitatively. MAIN RESULTS AND THE ROLE OF CHANCE: Quantitative results showed no differences between the groups on any demographic variables or in when or how they found out about being donor conceived, and no differences between active searchers and those open to contact in whether they had found their donor connections. Significant differences were found between groups in their interest in their genetic history and the perceived importance of genetics to their sense of identity, with active searchers being more interested and rating this as more important than those open to contact. Methods of searching significantly differed across groups, with active searchers using genetic testing and social media more than those open to contact. 59 participants across all groups (active searchers (n = 29, 74%), open to contact (n = 27, 61%), not open to contact (n = 3, 60%)) had found or been found by a donor connection. Experiences of finding or not finding donor connections among participants actively searching or open to contact were captured by the theme complexities, with six subthemes: uncertainties in searching and relating; searching as open-ended; different donor connections, different experiences; expectations and realities; searching and finding or not finding as catalysing change; and experiences of other donor conceived people. LIMITATIONS, REASONS FOR CAUTION: Most participants were members of relevant community organizations. As is common in research in this area, the sample was mostly female and conceived using donor sperm. Donor conceived people who are disinterested in donor connections may be unlikely to participate in research on this topic. WIDER IMPLICATIONS OF THE

findingsThe nature and impact of the search process itself should be considered when developing appropriate mechanisms of support for all donor conceived people, regardless of whether they are actively searching for connections or not. Further research should seek to better understand how donor conceived people with varying levels of interest in searching for donor connections differ from one another. STUDY FUNDING/COMPETING INTEREST(S): This study was funded by the UK Economic and Social Research Council [New Investigator Award ES/S015426/1]. The authors have no competing interests to declare. TRIAL REGISTRATION NUMBER: N/A.