ALSPAC is a longitudinal birth cohort study which enrolled pregnant women who were resident in one of three Bristol-based health districts in the former County of Avon with an expected delivery date between 1st April 1991 and 31st December 1992. Around 14,000 pregnant women were initially recruited. Detailed information has been collected on these women, their partners and subsequent children using self-completion questionnaires, data extraction from medical notes, linkage to routine information systems and from hands-on research clinics.
Additional cohorts of participants have since been enrolled in their own right including fathers, siblings, children of the children and grandparents of the children.
Ethical approval for the study was obtained from the ALSPAC Ethics and Law Committee (IRB00003312) and Local Research Ethics.