The analysis was made of the content of proteins in inflammation acute phase in 100 healthy puerperants and 157 women with endometritis after cesarean section. The established disproportion in protein concentration during acute phase in healthy puerperants is considered as a female organism adaptive reaction to pregnancy and delivery. As for patients with endometritis, this condition testifies the compensatory resources stress, development of pathophysiological reactions of organism and intensity of local damages. The concentration of C-reactive protein and prealbumin in patients with endometritis provides an opportunity to forecast the degree of severity of course of disease.