Is it acceptable to contact an anonymous egg donor to facilitate diagnostic genetic testing for the donor-conceived child?

We discuss a case where medically optimal investigations of health problems in a donor-conceived child would require their egg donor to participate in genetic testing. We argue that it would be justified to contact the egg donor to ask whether she would consider this, despite her indicating on a historical consent form that she did not wish to take part in future research and that she did not wish to be informed if she was found to be a carrier of a 'harmful inherited condition'. We suggest that we cannot conjecture what her current answer might be if, by participating in clinical genetic testing, she might help reach a diagnosis for the donor-conceived child. At the point that she made choices regarding future contact, it was not yet evident that the interests of the donor-conceived child might be compromised by her answers, as it was not foreseen that the egg donor's genome might one day have the potential to enable diagnosis for this child. Fertility consent forms tend to be conceptualised as representing incontrovertible historical boundaries, but we argue that rapid evolution in genomic practice means that consent in such cases is better seen as an ongoing and dynamic process. It cannot be possible to compel the donor to aid in the diagnosis of the donor-conceived child, but she should be given the opportunity to do so.