A typical feeding enhances memory for spoken words in healthy 2- to 3-day-old newborns.

OBJECTIVE: The objective of this study was to determine whether healthy 2- to 3-day-old newborns have better memory of a spoken word after a typical feeding (breast milk or formula) than before a feeding and, if so, whether memory is related to blood glucose. METHODS: A naturalistic study was conducted in which delayed recognition memory of a spoken word was examined in 60 healthy 2- to 3-day-old newborns either 120 minutes after their previous feeding (preprandial) or 30 minutes after their last feeding (postprandial). In this procedure, infants initially turn their head toward a novel word (orientation) and with repeated presentations cease turning toward it (habituation). Mean number of trials to reach orientation and habituation criteria provides measures of attention and rate of learning, respectively. After a 100-second delay, the word is presented again. Infants either turn toward it, indicating that they have forgotten it, or remain habituated, indicating that they remembered the word. Percentage of trials with head turns toward the word after the delay is the principal dependent measure. RESULTS: The postprandial group was split at the median for blood glucose to define high- and low-glucose groups. All 3 groups showed similar rates of orientation and habituation. On reexposure to the word during postdelay trials, the preprandial group displayed less retention than the postprandial high and low groups. No correlation was found between memory and blood glucose levels. The postprandial high blood glucose level differed statistically from the preprandial level, whereas the postprandial low level did not. CONCLUSIONS: Memory for spoken words in newborns is better after a typical milk feeding than before a feeding. This feeding effect is specific to memory and does not include attention or rate of learning. Also, it is not necessarily associated with increased blood glucose. It remains to be seen whether feeding enhances memory for other types of stimuli and what implications this may have for development.

Iron status in breast-fed infants.

Iron status of 30 infants who had been breast fed until their first birthday and who had never received cow milk, medicinal iron, or iron-enriched formula and cereals was investigated; 30% were anemic at 12 months of age. The duration of exclusive breast-feeding was significantly longer among nonanemic infants (6.5 vs 5.5 months). None of the infants who were exclusively breast fed for 7 months or more and 43% of those who were breast fed for a shorter time were anemic. Infants who were exclusively breast fed for a prolonged period had a good iron status at 12 and 24 months.

Breast-feeding and inguinal hernia.

A case-control study was conducted to study the association between breast-feeding and inguinal hernia. The case group was significantly less often breast fed than control subjects (odds ratio, 0.49; 95% confidence interval, 0.29 to 0.83) and exclusive breast-feeding was associated with a significant dose-response risk reduction. The association was not confounded by birth weight, maternal education, type of birth, number of other children in the family, or gender. Breast-feeding may represent a protective factor against inguinal hernia.