Cesarean section and offspring’s risk of multiple sclerosis: a Danish nationwide cohort study

• Published in: Multiple sclerosis Vol. 19; no. 11; pp. 1473 - 1477
• Main Authors: Nielsen, Nete M, Bager, Peter, Stenager, Egon, Pedersen, Bo V, Koch-Henriksen, Nils, Hjalgrim, Henrik, Frisch, Morten
• Format: Journal Article
• Language: English
• Published: London, England SAGE Publications 01.10.2013; Sage Publications; Sage Publications Ltd
• Subjects: Biological and medical sciences; Cesarean Section - adverse effects; Cohort Studies; Degenerative and inherited degenerative diseases of the nervous system. Leukodystrophies. Prion diseases; Denmark - epidemiology; Female; Humans; Male; Medical sciences; Multiple Sclerosis - epidemiology; Multiple sclerosis and variants. Guillain barré syndrome and other inflammatory polyneuropathies. Leukoencephalitis; Neurology; Pregnancy; Proportional Hazards Models; Risk Factors; Denmark; Europe; offspring; Multiple sclerosis; disease risk; immunology; C-section; mode of delivery; Human; Nervous system diseases; Birth; Inflammatory disease; Immunology; Cohort study; Central nervous system disease; Risk factor; Degenerative disease; Cesarean section
• ISSN: 1352-4585; 1477-0970; 1477-0970
• DOI: 10.1177/1352458513480010

Background: Apart from a recent study reporting a 2- to 3-fold increased risk of multiple sclerosis (MS) among women and men who were delivered by Cesarean section (C-section), little attention has been given to the possible association between mode of delivery and the risk of MS. Objectives: We studied the association between C-section and risk of MS, in a cohort of 1.7 million Danes born from 1973 to 2005. Methods: Information on C-section and MS was obtained from the Danish Medical Birth Register and the Danish MS Register, respectively. The association between C-section and MS was evaluated by means of MS incidence rate ratios (RR) with 95% confidence intervals (CI) obtained in log-linear Poisson regression analyses. Results: There were 930 cases of MS in the study cohort, of whom 80 (9%) were delivered by C-section. Overall, we found there was no significant association between C-section and risk of MS (RR = 1.17; 0.92–1.46). Analyses stratified by sex revealed no unusual risk of MS for women (RR = 1.08: 0.80–1.42) nor men (RR = 1.37: 0.91–1.98). A supplementary sibling-matched Cox regression analysis likewise suggested there was no excess risk of MS in persons delivered by C-section (HR = 1.03; 0.63–1.69). Conclusions: Mode of delivery appears to be unimportant in relation to MS development in the offspring.