News at Medicine - July 2012 - Study shows birth by C-section may increase risk for Type 1 diabetes in children

Study shows birth by C-section may increase risk for Type 1 diabetes in children
July 30, 2012
Results of a study conducted by researchers in the Faculty of Medicine and the Newfoundland and Labrador Centre for Health Information (NLCHI) indicate that delivery by caesarean section is associated with childhood onset of Type 1 diabetes in Newfoundland and Labrador.

Dr. Leigh Anne Newhook, Pediatrics, teamed up with NLCHI researchers Jennifer Phillips, Nicole Gill, Kohkan Sikdar and Sharon Penney with the Janeway Pediatric Research Unit to conduct this study, which was supported by a $30,000 Cox Award in 2009 from the Medical Research Endowment Fund (MRF). The results were recently published in the Journal of Environmental and Public Health.

Newfoundland and Labrador has one of the highest rates of Type 1 diabetes worldwide. Dr. Newhook said findings of this study indicate that birth by C-section was a significant risk factor for later development of childhood Type 1 diabetes. She said theories of why method of birth may be important include the role of early colonization of bacteria in the baby’s’ gut acquired during the birthing process and early development of the immune system.
“Studies have shown a difference between the compositions of gut microbiota in vaginally delivered children and those delivered by C-section,” she explained. “Another possible explanation is related to the hygiene hypothesis which proposes that the risk of diabetes may be increased when children are not exposed to infections early in life – children delivered by C-section have decreased neonatal infections compared to children born vaginally. Newfoundland and Labrador has a high rate of birth by C-section as compared to other regions of Canada.”

Cases of diabetes were identified using the Newfoundland and Labrador Diabetes Database (NLDD) for childhood diabetes, maintained by the Janeway Pediatric Research Unit. This database contains data on cases of Type 1 diabetes in children diagnosed from 1987 to present.

The Live Birth System, an administrative database maintained by NLCHI and containing data on all live births in Newfoundland and Labrador from 1992 to present, was used to obtain demographic data and clinical factors related to the risk factors of interest related to the pregnancy and birth.

Members of the Janeway Pediatric Diabetes Research Team have been studying the incidence of Type 1 diabetes in children in the province over the past two decades. Dr. Newhook said the team hope to research this association in greater detail to delineate if it is the mode of delivery that is important or other perinatal factors that led to C-section delivery.