Prenatal Maternal Bereavement and Its Association With Intellectual Disability in the Offspring

Source of Funding and Conflicts of Interest: X.S. is currently receiving a grant from the National Natural Science Foundation of China (81602860). Y.Y. is currently receiving a grant from the Lundbeck Foundation (R232-2016-2462 and R265-2017-4069). K.D.L. is currently receiving a grant from the Swedish Council for Working Life and Social Research (2015-00837). The study was supported by grants from the Independent Research Fund Denmark (DFF-6110-00019B and DFF-9039-00010B), the National Nature Science Foundation of China (82073570), the Nordic Cancer Union (R275-A15770), the Karen Elise Jensens Fond (2016), and the Novo Nordisk Foundation (NNF18OC0052029). All authors declare that there are no conflicts of interest. Copyright © 2021 The Author(s). Published by Wolters Kluwer Health, Inc. on behalf of the American Psychosomatic Society. ; OBJECTIVE: This study aimed to examine the association of a mother's loss of a close relative before or during pregnancy with intellectual disability (ID) in the offspring. METHODS: We performed a nationwide population-based cohort study based on Danish national registries. All live-born singletons born in Denmark during the 1978-2016 period (n = 2,216,601) were followed up starting from birth to 38 years of age. Log-linear Poisson regression was used to estimate the association between maternal bereavement (the death of an older child, a partner, or a parent 1 year before or during pregnancy) and the risk of ID in the offspring. RESULTS: Maternal bereavement during or before pregnancy was associated with an increased risk of ID (incidence rate ratio [IRR] = 1.15; 95% confidence interval [CI] = 1.04-1.28). The risk of ID was increased by 27% when maternal bereavement occurred during pregnancy (IRR = 1.27; 95% CI = 1.08-1.49). When stratifying on the child's sex, we also observed an increased risk of ID associated with maternal bereavement during pregnancy both for male (IRR = 1.25; 95% CI = 1.02-1.53) and for female (IRR = 1.31; 95% CI = 1.02-1.69), respectively. The IRRs for ...