Jørn Olsen,1 Zeyan Liew2
1Department of Clinical Epidemiology, Aarhus University Hospital, Aarhus N 8200, Denmark; 2Department of Environmental Health Sciences, Yale School of Public Health, Yale Center for Perinatal, Pediatric, and Environmental Epidemiology, Yale School of Public Health, New Haven, CT 06510, USA
Correspondence: Zeyan Liew
Department of Environmental Health Sciences, Yale School of Public Health, Yale Center for Perinatal, Pediatric, and Environmental Epidemiology, Yale School of Public Health, 60 College Street, New Haven, CT 06510, USA
Tel +1 203-764-9727
Abstract: In perinatal epidemiology, fetal deaths occur over the first timeline, from conception to birth or fetal death. Majority of other epidemiological research on human diseases focus on the second timeline, from birth to death. The transition from the first to the second timeline is not a fixed duration of time and it depends on when birth occurs. We discussed the complications when switching from the first to the second timeline in epidemiological studies of early life exposures, pregnancy events, and future health outcomes. Population-based studies often lack accurate data on the date of conception for most pregnancies and the complete count of fetal death, leading to chances for selection and misclassification biases. To address these problems, better research data and methodological advancement in study designs and biases evaluations are needed.
Keywords: fetal loss, miscarriage, bias, birth cohort, epidemiology
This work is published and licensed by Dove Medical Press Limited. The full terms of this license are available at https://www.dovepress.com/terms.php and incorporate the Creative Commons Attribution – Non Commercial (unported, v3.0) License.
By accessing the work you hereby accept the Terms. Non-commercial uses of the work are permitted without any further permission from Dove Medical Press Limited, provided the work is properly attributed. For permission for commercial use of this work, please see paragraphs 4.2 and 5 of our Terms.