Paper short abstract:

Birth cohorts provide a quintessential context for examining the corporeal quantification of bodies. We show how in this context numbers are made through shared labour, interembodied practices and socio-technical choreographies that render bodily quantifications as (un)stable, desired and normed.

Paper long abstract:

Quantification of the body is central to research in longitudinal birth cohort studies that follow participants, often intergenerationally from birth throughout their lives, to understand how social experiences and exposures effect development and social or health outcomes. Recording biometric data such as height, weight, body mass to more specialist measurements such as lung function to bone density are routine throughout the life course of cohort participants and their families. Even as birth cohorts are tools and technologies (Gibbon and Pentecost 2019) of emerging fields of biosocial research seeking to examine how the social becomes embodied, they would also seem to be a quintessential context for examining the corporeal quantification of the bodies . Drawing on an international ethnographic comparative study of birth cohorts ‘The Biosocial Lives of Birth Cohorts’ project and fieldwork in 4 regional birth cohort studies in Brazil, UK, Netherlands and Portugal this presentation examines how numbers are made in the routines of birth cohort data collection and how quantification is produced in the practice and collective labour of making and sustaining a birth cohort. Drawing on detailed ethnographic observations of the data collection with cohort participants where bodies are continuously enumerated we show how making numbers in birth cohorts is a reliant ‘interembodied’ (Bunkley 2022) practices that require complex choreographies (Cussins 1996) of technologies and multiple bodies, (both ‘counters’ and ‘counted’) and how numbers are simultaneously (un)stable, desired and normed.