Breastfeeding linked to infant temperament

In a cohort study of 316 babies aged 3 months, published in the journal PLoS One, breastfed infants were reported by their mothers to cry more and be harder to soothe than formula-fed babies.

Rather than being a sign of stress, the researchers say irritability is a natural part of the dynamic communication between mothers and babies and should not deter women from breastfeeding.

Lead researcher Dr. Ken Ong, a Paediatrician from the MRC Epidemiology Unit in Cambridge, said: “There is an overwhelming body of evidence supporting breastfeeding as the normal and most healthy form of infant nutrition and our findings do not contradict this. Bottle-fed babies may appear more content, but research suggests that these infants may be over-nourished and gain weight too quickly. Our findings are essentially similar to other stages of life; people often find that eating is comforting.

“Rather than being put off breast-feeding, parents should have more realistic expectations of normal infant behaviour and should receive better understanding and support to cope with difficult infant behaviours if needed. These approaches could potentially promote successful breastfeeding, because currently many mothers attempt to breastfeed but give up after the first few weeks.”

The Department of Health recommends that mothers exclusively breastfeed for the first six months after birth. According to the 2005 Infant Feeding Survey, three-quarters of new UK mothers start out breastfeeding their babies, but by four months this number has dropped to just one-third.

The most common reason given for women to stop breastfeeding is that “Breast milk alone didn't satisfy my baby”, which reflects their perception of irritability as a negative signal.

Professor Nick Wareham, Director of the MRC Epidemiology Unit, said: “This study does not provide evidence for causality, but it does give us some fascinating insights into the complex and dynamic signalling between mother and baby. Understanding the determinants of infant feeding is a key step in designing appropriate interventions aimed at supporting healthy behaviors.”

More information: The paper: Breastfeeding and infant temperament at age three months, by de Lauzon-Guillain et al, is published in the journal PLoS One.

Journal reference: PLoS ONE

Provided by Medical Research Council