Mother-infant skin-to-skin contact after delivery results in early recognition of own mother's milk odour.
OBJECTIVE
To determine the effects of mother-infant skin-to-skin contact immediately after birth on infant recognition of their own mother's milk odour and breastfeeding duration until 1 y of age.


METHODS
Sixty healthy, full-term neonates were randomly assigned to group A with skin-to-skin contact and group B without. One and 4 d after birth, infant responses to the following odour stimuli were observed: own mother's milk, another mother's milk, formula, orange juice and distilled water. Infant facial action was videotaped and the frequency of mouthing movements was evaluated for each stimulus. Nutritional assessment, focused particularly on breastfeeding, was performed every 3 mo on participating infants. Statistical analysis comparing the frequency of mouthing movements with the aforementioned five different odour exposures was performed by ANOVA with Fisher's PLSD. Kaplan-Meier analysis with a log-rank test was used to compare breastfeeding rates between groups.


RESULTS
Infants in both groups responded differently to mother's milk odour (either their own or another mother's milk) compared to the other stimuli on days 1 and 4. However, infants in group A demonstrated a larger difference in mouthing movements between their own and another mother's milk odour at 4 d of age (2.6 +/- 1.6) compared to infants in group B (0.9 +/- 2.0, p = 0.01). Infants in group A were breastfed an average of 1.9 mo longer than the others.


CONCLUSIONS
Our study provides evidence that mother-infant skin-to-skin contact for more than 50 min immediately after birth results in enhanced infant recognition of their own mother's milk odour and longer breastfeeding duration.
Mizuno
K
K
Division of Neonatology, Chiba Children's Hospital, Chiba, Japan. katsuorobi@aol.com
Mizuno
N
N
Shinohara
T
T
Noda
M
M
D000328:Adult; D001942:Breast Feeding / Q000523:psychology; D005149:Facial Expression; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D007743:Labor, Obstetric; D008297:Male; D008895:Milk, Human; D009034:Mother-Child Relations; D009812:Odorants; D011247:Pregnancy; D021641:Recognition, Psychology / Q000502:physiology*; D012867:Skin; D012903:Smell / Q000502:physiology*; D013997:Time Factors; D014110:Touch