A new meta-analysis suggests that the odour of maternal milk may have an analgesic action in newborn babies. The findings were published in the journal Breastfeeding Medicine.
Researchers conducted a meta-analysis of 8 randomised controlled trials (RCTs; n=453) identified through a literature search on the PubMed, MEDLINE, CINAHL, EMBASE, Web of Science and the Cochrane databases. The studies compared the effects of maternal milk odour on reduction of procedural pain in babies compared with scentless or other odours.
Babies exposed to maternal milk odour had lower pain scores (standardised mean difference [SMD], −0.81; P<.001 at the time of blood sampling and shorter crying afterwards p=".03)" compared with those exposed to scentless group. heart rate variability oxygen saturation during after a procedure were significantly lower in maternal milk odour group vs vanilla also babies had duration salivary cortisol levels formula odour.>
According to the authors, when newborn babies are exposed to their favourite milk odour the olfactory information is passed on to the hypothalamus and the hippocampus which mediates the emotional and motivational aspects of odours and subsequently induces physiological and behavioural calming action. They, however, call for further studies of high quality to confirm and quantitate the effect.