News article

UK Study on Infant Temperament May Simply Reflect Poor Breastfeeding Support

January 12, 2012

A study out of Cambridge UK by de Lauzon-Guilain et al found that exclusively breastfed infants in the county of Cambridgeshire were rated by their mothers to laugh less, cry more, and be more irritable than their formula-fed or mixed-fed counterparts. These results have puzzled and surprised many who do research in breastfeeding.

These surprising results, however, do not take into account one important factor that might be confounding their data— the mothers and infants are from a part of the UK where there are no Baby-Friendly hospitals and where maternity care practices around breastfeeding are suboptimal. Previous research has consistently shown that if mothers and babies are not getting off to a good start, mothers stop breastfeeding much sooner. Poor hospital practices are shown to associated with multiple breastfeeding difficulties, including suboptimal suckling.

Thus, it difficult to say if these infants are more distressed because of something inherent in breastfeeding itself, or simply because they were trying to breastfeed under difficult circumstances. Some observations in the study seem to indicate that it was the breastfeeding difficulties that may explain the results.

For example, the exclusively breastfed babies cried more. Crying is a late sign of hunger, and normally infants should be offered the breast well before they reach the crying stage. If the infant is having difficulties satisfying his needs, one would expect that he would score worse on just about every aspect of temperament. Additionally, if mothers are distressed because breastfeeding is not going well, they may perceive their infants to be more distressed.

“All we can really conclude from this study is that breastfed infants who were born in hospitals without evidence-based practices around infant feeding are more distressed than formula fed infants,” says Dr. Melissa Bartick, Chair of the Massachusetts Breastfeeding Coalition. “This is precisely the result one might expect from families trying it initiate breastfeeding in difficult circumstances.”

In order to see if there is something about breastfeeding itself that affects temperament, the study would have to be repeated in a setting where there are optimal maternity care practices around infant feeding. “In my experience, in developing countries where breastfeeding is the norm, it’s unusual to see a baby cry,” noted Bartick.