Sample selection
The CODIBINE cohort comprises all new-borns born with gestational age (GA)<37 weeks (n=7946) in Denmark between March 2009-March 2011, and maturely born controls with GA≥37 weeks (n=7946) matched by birth hospital and day. The blood samples were drawn from a heel prick as DBSS for routine new-born screening. Samples are shipped by mail and stored at the Danish New-born Screening Biobank, Statens Serum Institut, at -24°C after screening (24). Our cohort is linked with data from the Danish Medical Birth Register (MBR) (25) using the Danish Civil Registration System (26). This is the first of a series of papers from the project called CODIBINE, Correlations and Diagnoses for Biomarkers in New-borns, aiming to explore biomarkers in new-borns correlated to birth, complications and diagnoses later in life.
In the present study, we reduced the cohort to include mature births, with samples drawn 2-4 days after birth, in total 7266 individuals: 714 delivered by pre-labour CS, i.e. CS before onset of labour, 655 by in-labour CS, i.e. CS after initiation of labour, and 5897. Table 1 shows the demographic data for the mothers and new-borns.
Exclusion criteria were: active dissent to participation in scientific studies (as registered in the Danish national register for use of biological tissue, “Vævsanvendelsesregisteret”), lack of or insufficient sample material, incomplete civil registration number, and non-participation in the National New-born Screening Program.
The study was supported by ”Læge Sofus Carl Emil Friis og hustru Olga Doris Friis’ legat” and ”Fonden til Lægevidenskabens Fremme”. The warded grant did not include external peer review for scientific quality or priority assessment. The funders were not involved in conducting research and writing the paper.