title: Psychosocial stress related to the loss of a close relative the year before or during pregnancy and risk of preeclampsia.
abstract: The role of stress in the pathogenesis of preeclampsia has only been investigated in a few studies, and the findings are not conclusive. We analyzed whether maternal bereavement shortly before or during pregnancy is associated with an increased risk of preeclampsia. We conducted a cohort study of singleton births in Denmark during 1978-2008 and in Sweden during 1973-2006 (n=4 122 490) by linking national population-based registers. Mothers were considered exposed to bereavement if they lost a parent, a sibling, a partner, or a child the year before or during pregnancy (n=124 553). The risk of preeclampsia was slightly increased for women who lost a close relative during the 6 months before conception (odds ratio [OR], 1.14; 95% confidence interval [CI], 1.06-1.23) or during the first trimester of pregnancy (OR, 1.15; 95% CI, 1.03-1.29). Exposure during these periods tended to be more closely related to early preeclampsia (delivery before 34 weeks of gestation; OR, 1.37; 95% CI, 1.12-1.67) than to late preeclampsia (OR, 1.13; 95% CI, 1.06-1.20). The strongest association was observed between loss of a child and early preeclampsia when the exposure window was from 6 months before pregnancy until start of second trimester (OR, 4.03; 95% CI, 2.46-6.61). Our results related to timing of exposure suggest that severe stress may influence early placentation. However, the public health implications of our findings are limited in populations with a low prevalence of severe stress exposures.
authors.affiliation: Department of Medicine, Clinical Epidemiology Unit, Karolinska University Hospital and Karolinska Institute, Stockholm, Sweden. krisztina.laszlo@ki.se
authors.forename: Krisztina D
authors.initials: KD
authors.lastname: László
authors.forename: Xiao Qin
authors.initials: XQ
authors.lastname: Liu
authors.forename: Tobias
authors.initials: T
authors.lastname: Svensson
authors.forename: Anna-Karin
authors.initials: AK
authors.lastname: Wikström
authors.forename: Jiong
authors.initials: J
authors.lastname: Li
authors.forename: Jørn
authors.initials: J
authors.lastname: Olsen
authors.forename: Carsten
authors.initials: C
authors.lastname: Obel
authors.forename: Mogens
authors.initials: M
authors.lastname: Vestergaard
authors.forename: Sven
authors.initials: S
authors.lastname: Cnattingius
mesh_terms: D000328:Adult; D003718:Denmark / Q000453:epidemiology; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007231:Infant, Newborn; D008297:Male; D011225:Pre-Eclampsia / Q000453:epidemiology / Q000209:etiology* / Q000503:physiopathology; D011247:Pregnancy; D011256:Pregnancy Outcome; D015995:Prevalence; D011379:Prognosis; D011446:Prospective Studies; D012042:Registries; D013315:Stress, Psychological / Q000150:complications* / Q000453:epidemiology; D013548:Sweden / Q000453:epidemiology; D013997:Time Factors; D055815:Young Adult
keywords: bereavement; cohort study; placentation; preeclampsia; psychological stress