Researchers at the Leverhulme Centre for Demographic Science (LCDS) have released a new working paper examining mortality patterns in the intersex population, the first study of its kind to address this topic using large-scale registry data.
The paper, Mortality Patterns in the Intersex Population, is authored by Morten Kjær Thomsen, Andrea Tilstra, and Jane Greve. Two of the authors, Dr Thomsen and Dr Tilstra, are researchers at LCDS, and Dr Greve recently visited the Centre to collaborate on this groundbreaking project and to present her work in a seminar during Michaelmas term.
The study provides the first population-level analysis of mortality patterns among intersex individuals — those whose sex characteristics do not align with typical notions of male and female bodies — shedding light on a population that has historically been invisible in demographic research. Using Danish administrative data covering nearly three decades, the authors identify more than 1% of the population as having intersex traits.
The results reveal distinctive life-course patterns. Intersex males experience slightly higher mortality in early life, mainly linked to congenital conditions, but show lower mortality than sex-typical males in mid-to-late adulthood. In contrast, intersex females face higher mortality risks later in life compared to sex-typical females, particularly from cardiometabolic causes. Overall, mortality patterns among intersex individuals fall -- like their sex characteristics -- between those typically observed for males and females.
Dr Thomsen, lead author of the study, commented: “Demography as a field has had remarkably little to say about intersex people, primarily because we lacked the tools and data to study this relatively large population at scale. This paper changes that. For the first time, we can describe how intersex individuals live and die across the life course, and the patterns we find challenge established patterns of male and female mortality. We hope this opens the door to a richer conversation about sex, health, and inequality in population research.”
The study builds on a novel strategy for identifying intersex individuals in administrative data, developed by Dr Thomsen and Dr Greve in a previous paper (link to pre-print: https://osf.io/preprints/socarxiv/wg4dt_v2). By applying this approach in the context of mortality for the first time, the authors demonstrate its potential to open up entirely new lines of inquiry into the health and lives of intersex populations.
The working paper was released during LGBT+ History Month, underscoring the broader significance of the findings for understanding inequalities and promoting inclusive research practices.
The preprint is available online.
