Introduction:
Delivery is a physiological process stimulating the adaptation of the newborn to new conditions of life outside the mother’s body The moment of the baby’s birth and cutting the umbilical cord means the newborn’s violent transition from the uterine environment to the external world, which requires the dynamic process of adaptation connected with numerous physiological states of transient character. The degree of the intensification of the transient states may still be different and cause deviations from the norm, or even transition into pathological states constituting the cause of a prolonged stay in hospital, invasive examinations and longterm treatment.

Objectives:
The aim of the study was a comparative analysis of the intensification of the chosen transient states in the newborns born naturally, and those born through Caesarean section.

Material and methods:
In August-September 2018, 148 women and 148 newborns were qualified to the study. The exclusion criteria were mother’s chronic diseases diagnosed before the pregnancy, delivery before the 37th week, negative blood group of the mother, and the newborn’s Apgar result below 10 points.

Results:
The newborns born naturally were more frequently fed only naturally (N- 55; 67.9%), in comparison to those born through caesarean section (30; 44.7%). The body weight loss expressed in % in relation to the birth body weight in the group SN reached 5.45%, while in group CC – 6.26% (p=0.01275).

Conclusions:
The newborns born naturally were more often fed naturally than those born through caesarean section. The physiological weight loss in the first days was greater in newborns born via caesarean section than those born naturally