MedWire News: Asthmatic mothers who take their babies swimming in early life may be increasing their child's risk of wheezing, findings from a Norwegian study suggest.

"It is hypothesised that there may be a causal relationship between environmental exposures from baby swimming in indoor pools and infant respiratory health outcomes," explain Dr Wenche Nystad, from the Norwegian Institute of Public Health is Oslo, and colleagues.

Indeed, some studies have suggested that exposure to the chemical chlorine, which is used as a disinfectant in swimming pools, may increase the risk of asthma in susceptible children, they add.

To examine the effects of baby swimming in the first 6 months of life on respiratory diseases between the ages of 6 and 18 months, the team analysed data from a study of 30,870 children who were born between 1999 and 2005.

Surveys completed by the mothers showed that 25% of their children had attended baby swimming sessions in the first 6 months of life.

Analysis revealed that, overall, children who attended baby swimming sessions were a 'non-significant' 8% more likely to suffer from respiratory infections, wheezing or otitis media (ear infection) between 6 and 18 months of age than those who did not attending baby swimming sessions.

However, further analysis showed that children of asthmatic or allergic mothers who attended baby swimming sessions were around 24% more likely to suffer from wheezing between the ages of 6 and 18 months than children without asthmatic mothers who did not attend baby swimmming sessions.

Among children of asthmatic or allergic mothers, those who attended baby swimming sessions were around 4% more likely to suffer from wheezing than those who did not.

"The results of this study suggest that some children have an increased risk of wheeze if they take part in baby swimming during infancy. However, the risk of lower respiratory tract infections or otitis media was not increased," the researchers conclude in the journal Acta Paediatrica.