Is the length of work careers determined in utero?

Low weight at birth increased the risk of disability pension among men, reveals a new Finnish study published in the PLoS One. Around 20% of the cohort members born in 1934–44 retired on a disability pension between 1971 and 2011.

"Early exit from the workforce due to a disability pension might be related to non-optimal growth during the fetal period," says Docent Mikaela von Bonsdorff from the University of Jyväskylä.

The leading causes of disability pension are mental disorders, musculoskeletal disorders and cardiovascular diseases. Low birth weight was particularly associated with a higher risk of disability pension due to mental disorders.

"The average retirement age of cohort members who retired due to mental disorders was 51, whereas other cohort members were able to work 10 years longer. This is a substantial loss to the economy," says Mikaela von Bonsdorff from the University of Jyväskylä.

The Helsinki Birth Cohort Study includes birth and childhood growth data extracted from the medical and healthcare records of 13,500 individuals. The Finnish child welfare system, established already in the 1930s, has enabled unique research on how early physical development and growth is associated with adult chronic diseases, ability to function and premature mortality.

"These findings emphasise that early development and growth has various long-term consequences for public health and the economy. Suboptimal intrauterine development might increase susceptibility to adulthood mental disorders causing early exit from the workforce," says Professor Johan Eriksson, the leader of the Helsinki Birth Cohort Study from the University of Helsinki.

The research is related to Mikaela von Bonsdorff's postdoctoral researcher project "Early physical development, growth and work career as determinants of old age health and functioning – Life course epidemiology," funded by the Academy of Finland.