Is maternal obesity in pregnancy a risk factor of asthma in offspring?

Published Online: November 5, 2012

Parallel to the rising obesity prevalence world-wide, an increase in allergic diseases has been observed over the last decades. Obesity is considered to be a condition with chronic low-grade systemic inflammation, and previous studies suggest a link between maternal obesity and/or excess weight gain during pregnancy and later development of asthma and wheezing in the child. However, the studies are sparse and do not provide a comprehensive insight into the impact of both BMI and gestational weight gain (GWG) within the same individuals on both respiratory and allergic diseases in children and taking into account childhood body mass index (BMI) and atopic sensitization.

In a recently published original article in The Journal of Allergy and Clinical Immunology, Harpsøe et al investigated the effect of maternal obesity and weight gain during pregnancy on the offspring’s health in a large-scale prospective cohort study based on interviews during and after pregnancy from the Danish National Birth Cohort. The study included 38,874 mother-child pairs followed from pregnancy until the child was 7 years old.

The impact of maternal pre-pregnancy BMI and gestational weight gain on the development of asthma, wheezing, atopic eczema, and hay fever in the child during the first 7 years of life was examined. Extensive information was available on a great number of factors, such as sex of the child, maternal age, maternal smoking in pregnancy, number of older siblings, maternal history of allergy, gestational age, birth weight, breastfeeding, and child BMI at 7 years of age.

The researchers found maternal BMI and to a lesser extent GWG to be associated with doctor-diagnosed asthma.In particular, children of mothers with BMI ≥ 35 and GWG ≥ 25 kg were at increased risk of current severe asthma at age 7 years. High maternal BMI was also associated with especially late-onset wheezing in offspring. For both asthma and wheezing the strongest associations were found in non-atopic children. Oppositely, maternal BMI and GWG were not associated with the allergic diseases, atopic eczema, and hay fever. The authors therefore suggest a non-allergic pathway between maternal inflammatory changes caused by obesity and the development of asthma and wheezing in the offspring.

The Journal of Allergy and Clinical Immunology (JACI) is the official scientific journal of the AAAAI, and is the most-cited journal in the field of allergy and clinical immunology.

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