[Formation of respiratory system function in ontogeny. I. Intrauterine respiratory movements]

The fetus rhythmic respiratory movements originate long before the birth at a certain stage of its intrauterine development, i. e. the rhythmic respiratory activity is formed before the delivery. As the fetation takes place the character of respiratory system rhythmic activity shifts to stabilization of respiratory muscles rhythmic action towards the termination of gestation. The fetal respiratory movements are inhibited with the beginning of the generic act.