The relationship between salivary and colostrum cortisol concentrations, assessing adiposity in healthy mother/newborn dyads on the first postpartum day: a preliminary study.

Objective

To explore the relationship between salivary cortisol concentration in newborns and salivary and milk cortisol concentration in their mothers with indicators of adiposity on the first day of life.

Methods

This was a cross-sectional study on 39 dyads on the first postpartum day. Healthy mothers aged 18-35 years with a full-term pregnancy and a normal delivery of newborns with adequate weight for gestational age. Samples for salivary cortisol of the dyads and mothers' milk were collected between 7-8 AM. Cortisol quantification was performed by ELISA. The adiposity and length of newborns were assessed by anthropometric measurements and areas. Maternal adiposity was assessed through anthropometry and electrical bioimpedance. Numerical data were analyzed with parametric statistics.

Results

Direct linear significant correlations and regressions for cortisol concentrations of dyads with indicators of adiposity and length in newborns and adiposity in mothers were found. The relationship between the cortisol concentration in both newborns and mothers with adiposity was stronger for arm indicators, mainly the arm fat area. There was no association between the concentration of cortisol in newborn saliva and that in mothers. The concentration of cortisol in colostrum showed a slight correlation with the arm fat area.

Conclusions

A relationship between cortisol concentration and adiposity in dyads was demonstrated. Cortisol may play a role in facilitating greater independent energy fat reserves as an adaptive factor in the early postnatal period.