Caesarean ups asthma risk in kids

Babies born by Caesarean section may be more likely to develop asthma than babies born vaginally, the results of a new study indicate.

Rates of asthma and the number of women having Caesarean sections have both soared in industrialised countries in recent years. In Ireland alone, one in five children has asthma and almost one in four births is by Caesarean.

A team of Swiss researchers monitored the respiratory progress of almost 3,000 children until they reached the age of eight. They found that by the time the children were eight, 12.4% had been diagnosed with asthma for which they had been prescribed inhaled steroids.

While just 8.5% of the children had been born by Caesarean section, they were almost 80% more likely to have been diagnosed with asthma compared to their vaginally delivered peers.

This association was even stronger for those children with two allergic parents and therefore a strong genetic predisposition to the condition.

The researchers suggested that the link between Caesarean section births and an increased risk of asthma may be to do with the timing of the priming of the immune system – Caesarean deliveries delay exposure to microbes.

While previous studies on this same topic have produced conflicting results, the researchers believe these findings are valid due to the number of children involved, the long monitoring period and the definition of asthma to include inhaled steroids.

“The increased rate of Caesarean section is partly due to maternal demand without medical reason. In this situation, the mother should be informed of the risk of asthma for her child, especially when the parents have a history of allergy or asthma,” they added.

Details of these findings are published in the medical journal, Thorax.

For more information on asthma, see...http://www.irishhealth.com/clin/asthma/index.html

For more information on pregnancy, see...http://www.mum.ie

[Posted: Tue 02/12/2008]