Early life experiences may have enduring effects on human biological development. Premature infants aged 6 to 12 months cared for in incubators (control group, C) shortly after delivery were compared with premature newborns cared for using the kangaroo method (experimental group, E), characterized by consistent skin-to-skin contact. We found that groups C (n = 15) and E (n = 27) were comparable at birth. Logistic regression analysis showed that Group C infants had higher salivary cortisol concentrations and were shorter as compared with Group E infants. These findings are consistent with experimental findings showing that differences on early maternal presence lead to enduring biological consequences.