CONCLUSIONS
When the ADHD hazard was averaged over the duration of the study’s follow-up, there was no association between prenatal SSRI/SNRI exposure and ADHD in offspring, and exposure misclassification could biased our results towards the null only modestly. The risk for child ADHD following prenatal SSRI/SNRI exposure was elevated only at age 7-9 years. The lack of a clear duration-related relationship, and the observed confounding by maternal psychiatric indicators in this study, does not support a causal link between SSRI/SNRI and child ADHD. Future research is needed on the age-specific associations between antidepressants in pregnancy and ADHD subtypes trajectories.
Acknowledgments: The Norwegian Mother, Father and Child Cohort Study is supported by the Norwegian Ministry of Health and Care Services and the Ministry of Education and Research. We are grateful to all the participating families in Norway who take part in this on-going cohort study.
Funding : This project is funded through the HN’s ERC Starting Grant “DrugsInPregnancy” (grant no. 678033). EY is supported by the Norwegian Research Council (grant no. 262177 and 288083). AL is supported by the Norwegian Research Council (grant no. 288696). The funders had no role in the analyses, interpretation of results, or the writing of this manuscript.
Disclosure of interest: no conflicts to declare.
Contributions of authors: HN and MH conceived the study and applied for the study data. AL performed the data analysis, and MM contributed to data curation. AL wrote the initial draft. AL, MM, MH, HN, EY, and TRK contributed to data interpretation and to writing the final manuscript. HN obtained funding. The corresponding author attests that all listed authors meet authorship criteria and that no others meeting the criteria have been omitted.
Details of Ethics Approval : The establishment of MoBa and initial data collection was based on a license from the Norwegian Data protection agency and approval from The Regional Committees for Medical and Health Research Ethics. The MoBa cohort is based on regulations based on the Norwegian Health Registry Act. The current study was approved by The Regional Committees for Medical and Health Research Ethics on 26th March 2015 (reference number: 2015/442/REK Sør-Øst).

Patient and public involvement

We did not include patient and public directly throughout the research process (formulation of research questions, outcome measures development, study design, recruitment, the conduct of the study, and dissemination of the results).