Risk of suffering from pre school wheezing gets reduced by almost half in babies, who start eating fish before they turn nine months, a new study has suggested. But they face a higher risk if they are treated with broad-spectrum antibiotics in the first week of life or their mother takes paracetamol during pregnancy. Researchers analysed responses from 4,171 randomly selected families, who answered questions when their child was six months, 12 months and four-and-a-half years of age. "Recurrent wheeze is a very common clinical problem in preschool children and there is a need for better medical treatment and improved understanding of the underlying mechanisms" said lead author Dr Emma Goksor from the Queen Silvia Children's Hospital, University of Gothenburg, Sweden. "The aim of our study was to identify both important risk factors and protective factors for the disease." "Our demographic analysis suggests that the responses we received were largely representative of the population as a whole and we believe our findings provide useful information on three important factors involved in pre-school wheeze." The study examined children who had had three or more episodes of wheezing in the last year, including those who did and did not use asthma medication (inhaled corticosteroid), and compared them with children who did not wheeze. The study revealed that one in five of the children had at least one episode of wheezing and one in 20 had recurrent wheeze (three or more episodes) over the last year. Of these, three-quarters had used asthma medication and just over half reported doctor-diagnosed asthma. More than half of the children with recurrent wheeze had episodic viral wheeze (57per cent) and 43per cent had multiple-trigger wheeze. The study also found that eating fish before the age of nine months almost halved the likelihood of suffering recurrent wheeze at 4.5 years. The fish most commonly eaten was white fish, followed by salmon and flat fish. On the other hand, being treated with broad-spectrum antibiotics in the first week was associated with double the risk of recurrent wheeze at 4.5 years. Just 3.6per cent of the children in the no wheeze group had received antibiotics, compared with 10.7per cent of those who had experienced three or more episodes. It was further revealed that less than a third of the mothers (28.4per cent) had taken some medication during pregnancy, with 7.7per cent of the total taking paracetamol and 5.3percent only taking paracetamol. The prevalence of prenatal paracetamol exposure in the wheeze group using asthma medication was 12.4per cent and taking paracetamol during pregnancy increased the risk by 60per cent. The study has been published in Acta Paediatrica.