The analysis of cord blood could make it possible to evaluate the risk of respiratory diseases of the child later in life, underlines this study of La Trobe University (Melbourne) presented in the journal Environment International. One result in particular stands out: exposure to pollen during pregnancy may be linked to the risk of asthma in the baby. But it is one factor, among many possible factors that can favor the development of asthma or allergies.
Many studies have shown that babies with high levels of Immunoglobulin E (IgE) in cord blood can develop allergies later in childhood, but little is known about how these levels are affected by exposure to pollen in utero. This analysis of cord blood taken from hundreds of babies born in Melbourne, Denmark and Germany, essentially shows that children born during the season of maximum exposure to grass pollen are at greater risk of developing respiratory diseases. such as asthma.
- "We knew that exposure to pollen during the first two months of life can lead to a higher vulnerability to allergic respiratory diseases, our study suggests that maternal exposure in the later stages of pregnancy could also be decisive", comments the lead author, Dr. Bircan Erbas. Thus, in Melbourne, researchers find high levels of IgE in babies born in October and December, in Germany and Denmark, this is the case in babies born in April, the month of strongest pollination in Europe.
- However, the study also finds that a pregnancy “locked” to the whole of the grass pollen season can have a protective effect on the babies: in this case, the IgE levels are lower in the babies. A significant discovery that suggests the possible development of a “sensitization barrier”.
Further research into periods of risk for pollen exposure during pregnancy will be conducted, although the period of pregnancy cannot always be chosen and although not all babies born during a high pollination season will develop disease. respiratory or allergic.
However, on an epidemiological level, the study provides new information that can help better manage diseases such as asthma, which represent a significant public health burden.