Presuming parentage in lesbian – as in heterosexual – couples? Equal treatment claims before the European Court of Human Rights: Boeckel and Gessner-Boeckel v Germany , and R.F. and Others v Germany

It is increasingly common in married or registered lesbian couples to conceive children through assisted reproduction with donor sperm. In these families, parentage is automatically attributed to the woman giving birth, while the birth mother’s spouse or partner – sometimes even the egg provider – must typically undergo adoption to be recognised as the other parent. This starkly contrasts with heterosexual couples in which the birth mother’s spouse is the other parent by virtue of the presumption of legitimacy, without further steps, sparing stakeholders from legal uncertainty, costs, and emotional strain. This article examines how the European Court of Human Rights responds to claims of alleged discrimination caused by this disparity, with particular attention to Boeckel and Gessner-Boeckel v Germany and R.F. and Others v Germany. It argues that ‘biological differences’ between the couples are insufficient to explain the unequal treatment. At the same time, it considers whether such unequal treatment can be justified on grounds of collective interests, drawing on broader case law under the European Convention on Human Rights, where it provides necessary contextual background for specific points of the analysis. It concludes that, in certain circumstances, States retain discretion to refuse a gender-neutral extension of the presumption of legitimacy and thereby perpetuate the systemic imbalance in their family laws.