Prenatal alcohol exposure (PAE) associated with fetal alcohol spectrum disorders (FASD) often remain underdiagnosed. They globally cause a wide range of health and social problems leading to high costs. To outline cumulative health and social care costs in children related with PAE with and without diagnosed FASD, we followed 427 children with PAE until the age of 20 years, and 1795 controls born 1992-2001 until the year 2016. All hospital care and out-of-home care episodes were analyzed, and their costs estimated. Age-dependent patterns of diagnoses and costs of those with PAE with and without diagnosed FASD were compared to controls. Children with PAE had significantly higher risks and hospital costs for both somatic and psychiatric conditions compared with controls. Mean cumulative hospital costs were 55 500€ (IQR, interquartile range, 56 800€) for PAE with FASD, 30 100€ (IQR 25 100€) for PAE without FASD and 15 600€ (IQR 12 000€) for controls. Between 0 to 10 years, FASD was associated with higher somatic costs, whereas psychiatric costs dominated in the PAE without FASD group. FASD diagnosis was associated with lower risks of traumatic injuries, substance use disorders, and teenage pregnancies, independent of early out-of-home care, which was associated with FASD.  Out-of-home care was common in PAE groups, and its costs far exceeded hospital costs: mean cumulative costs were 30-fold in FASD (610 000€, IQR 375 800€) and 17-fold in others with PAE (344 300€, IQR 621 900€) compared to controls (20 500€, IQR 0€). Health and particularly social care costs associated with PAE are significant. High out-of-home care costs reflect substantial needs for support and rehabilitation for birthmothers with alcohol consumption during and after pregnancy. Early diagnosis of FASD may mitigate secondary complications and associated costs emerging in adolescence.  Prevention policies are urgently needed at primary, secondary and tertiary level.

The authors have declared no competing interest.

The author(s) received no specific funding for this work.

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The study was approved by the Hospital district of Helsinki and Uusimaa (HUS400/2016). The authorities maintaining the registers approved the use of data for this study project. The register linkages, accessing data until 31. December 2016, and pseudonymization of the data were conducted by the Finnish Institute of Health and Welfare (THL) as the statistical authority. Therefore, the researchers did not access the registers directly and could not identify individual subjects. Because 1) study subjects were not contacted, 2) the study was considered to be of public health importance, 3) the number of participants was large, and 4) the research was done using official permission, according to the Finnish legislation (the Medical Research Act (488/1999)) the research was not considered medical research. Following this, separate statement from ethics committee or informed consent from the subjects were not required.

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