MedWire News: Individuals born by Cesarean section are about 20 percent more likely than those delivered by other methods to develop childhood-onset type 1 diabetes, an extensive meta-analysis shows.

The association between cesarean section and type 1 diabetes could not be explained by potential confounders, including gestational age, birth weight, maternal age, birth order, breastfeeding, and maternal diabetes, the researchers report.

However, study author Chris Patterson, from Queen's University in Belfast, UK, said the findings are "interesting" but cautioned: "Unless a biological mechanism is established it would be unwise to read too much into this association.

He added: "Fortunately figures from the Northern Ireland type 1 diabetes register indicate that only around two per 1,000 children will develop diabetes by their 15th birthday, so a 20 percent increase is on quite a low baseline risk."

Lead author Chris Cardwell, also from Queen's University, and colleagues analyzed data from 20 published studies from 16 countries, including around 10,000 children with type 1 diabetes and over a million without it.

Overall, they found a significant 23 percent increase in risk for type 1 diabetes in children born by caesarean section, compared with those delivered by other methods.

This increase in risk fell to a significant 19 percent after adjustment for confounders, and there was little evidence of heterogeneity between studies, the authors note.

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