The experiments were conducted on sexually mature female white mongrel rats weighing 170-190 g. The model of toxic hepatitis in the experimental animals was obtained by weekly administration of heliotrin at a rate of 0.5 mg/100 g of animal weight for 6 weeks. Ten days after the last injection, males were added to the females. The experimental animals were rat pups aged 3, 7, 14, 21 days, born and nursed by female mothers with chronic toxic hepatitis. These study periods are consistent with the generally accepted division of age periods in rats: neonatal period (1-5 days), suckling period (6-21 days). The work was carried out in accordance with the "Rules for Carrying Out Work Using Laboratory Animals". Animals were decapitated under ether anesthesia. The control group consisted of rat pups born and nursed by healthy intact females, which were given the corresponding amount of isotonic solution instead of heliotrin at the same time. For the study, pieces were taken from the stomach, small intestine, large intestine and liver of control and experimental animals on the 3rd, 7th and 21st days of postnatal life. The isolated material from the organs was fixed in a 10% solution of neutral formalin and Carnoy's fluid. The obtained material was subjected to morphological, morphometric and electron microscopic methods of study. In the course of experimental studies, the effect of chronic liver pathology in the mother on the postnatal morphogenesis of the gastrointestinal tract organs of the offspring was revealed. Experiments have shown that toxic hepatitis of the mother will negatively affect the postnatal growth, development and formation and the morphofunctional state of the vascular-tissue structures of the gastrointestinal tract and liver of the offspring, causing pathomorphological changes in their vascular-tissue structures, which subsequently lead to a lag, a delay in the processes of postnatal development and their formation. All this determines the need to develop scientifically based therapeutic and preventive measures in relation to children born and nursed by mothers with liver pathology, in order to prevent the consequences of development.