Breastfeeding, Maternal Asthma and Wheezing in the First Year of Life

Study shows when moms with asthma breastfeed longer, their babies are less likely to wheeze

Article Title: Breastfeeding, Maternal Asthma and Wheezing in the First Year of Life: A Longitudinal Birth Cohort Study
Journal: European Respiratory Journal  
Date: May 1, 2017

Researchers sought to understand the impact breastfeeding has on respiratory health, particularly when the mother has asthma. The study involved 2,773 mother-infant pairs, grouped into one of three groups: exclusive breastfeeding, no breastfeeding and partial breastfeeding. The partial breastfeeding group was broken down into two sub groups: those who supplemented with formula and those who supplemented with complementary foods. Caregivers then reported on infant feeding and wheezing episodes at three, six and 12 months of age.

For the mothers who had asthma (21%), infant wheezing was reduced by breastfeeding. These results were independent of maternal smoking status, education level and other risk factors.

The group that exclusively breastfed for six months saw wheezing reduced by 62%, when compared to the no breastfeeding group. Babies in the partial breastfeeding group that supplemented with complementary foods showed infant wheezing was reduced by 37%, when compared with no breastfeeding. However, when infant breastfeeding was supplemented with formula, there was no significant protection against wheezing – in spite of having been partially breastfed.

Key takeaways/Why this is important:
Wheezing is one of the most common reasons infants see a healthcare provider or are hospitalized. Early wheezing is a risk factor for asthma and chronic obstructive pulmonary disease later in life. Even transient wheezing is associated with reduced lung function and increased asthma risk in adolescence. Finding ways to prevent or reduce early wheezing is an important public health priority.

This study strengthens the evidence that breastfeeding provides protection against wheezing in early life and identifies new information:

  • The longer and more exclusive the mothers breastfed, the stronger the protection from wheezing. This was especially true if the mother had asthma herself.
  • An unexpected finding was that breastfeeding is more protective against wheezing in male infants. Being born male is a well-known risk factor for infant wheezing, which highlights the importance of considering sex differences in breastfeeding research.
  • If babies were fed complementary foods before six months of age, partial breastfeeding was a little more than half as protective against wheezing as exclusive breastfeeding.
  • If babies were fed supplemental formula before six months of age, the benefits of partial breastfeeding did not confer significant protection against wheezing.

Breastfeeding is an effective way to prevent infant wheezing and promote lifelong respiratory health. This study contributes to the growing base of knowledge about the multiple, substantial health benefits it confers.

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The OHSU Bob and Charlee Moore Institute for Nutrition & Wellness supports human research that seeks to find the links between maternal stresses, including poor nutrition, and elevated disease risks for babies as they become adolescents and adults.


Azad MB, Vehling L, Lu Z, et al. Breastfeeding, maternal asthma and wheezing in the first year of life: a longitudinal birth cohort study. Eur Respir J 2017; 49: 1602019 [].