Breastfeeding strengthens maternal bond

Mothers who exclusively breastfeed their babies for the first 2 to 4 weeks of life are more likely to have a stronger emotional bond with their child during the first few months of life than mothers who exclusively formula-feed, say the findings of a new study.

Researchers placed 17 Caucasian biological mothers of healthy infants into 1 of 2 groups: either exclusive breastfeeding or exclusive formula feeding for 2 to 4 weeks postpartum. They excluded women with birth complications, current psychiatric diagnoses, or a history of prescription medications taken within 2 weeks of the experiment. Both groups were relatively well matched for parenting experience, age, handedness, number of children, and delivery method, but because maternal education was higher in the breastfeeding group, maternal education level was included as a covariate in comparing the 2 groups' brain responses at 2 to 4 weeks postpartum.

Researchers then performed MRI scans on the women at 1 month postpartum to examine maternal brain activation in response to their own baby's cry versus another baby's cry. They also videotaped dyadic interactions between the mothers and their infants at 3 to 4 months postpartum in the home and blindly coded them for maternal sensitivity. They found that in the first month postpartum, breastfeeding mothers showed greater activation in brain regions known to be important in caregiving and empathy, including the superior frontal gyrus, insula, precuneus, striatum, and amygdala, in response to their own baby's cry versus another baby's cry, and that these women had higher maternal sensitivity at 3 to 4 months postpartum.

Kim P, Feldman R, Mayes LC, et al. Breastfeeding, brain activation to own infant cry, and maternal sensitivity. J Child Psychol Psychiatry. April 18, 2011. [Epub ahead of print.]