[Etiology of congenital abnormalities].

In this work the author presents his own views regarding the etiology of congenital deformations. The development has been classified according to three phases, taking account of the influence of exogenic and/or endogenous noxae and their secondary effects: 1. The phase between the primordial cell and the second mature cell division; 2. the phase between the second mature cell division and the 12th week of the embryo; 3. the phase following the 12th week of the embryo. During the first phase we are confronted with chromosomal and genetic disturbances. During the second phase, we see disturbances in the process of differentiation and in the third phase anomalies in terms of growth.