Abstract Pre parturion and newborn period events like infecous stresses have important effects on the future life of an offspring. LPS can be a cause of bacterial stress in the body. Silymarin is an herbal substance that has some therapeuc effects on body. According to our literature review there was no any study available about silymarin preservave and useful effects aſter LPS intervenon on fetuses in their future life. Mice of both sex with 25–30 g weight were kept with each other for breeding and the first day of pregnancy was ascertained by observaon of vaginal plaque. Silymarin was suspended in normal saline and then administered to pregnant mice (100 and 250 mg/kg) by stomach gavage for 5 days. Pregnant mice received LPS by one intraperitoneal injecon (300 and 500 µg/kg). Half of the offspring’s were used for blood sampling for immunologic tests 1.5 hour aſter immune system smulaon (IP injecon of LPS with the dosage of 500 µg/Kg in the day 67 aſter their birth) IL-1β, TNF-α and IL-6 were measured in them with indirect ELISA kits .Another half of the liers were killed in 70 th day of their life (aſter 3 days of new LPS injecon) and whole brain and a specimen from their leſt lobe of liver was put into neutral buffered formalin. LPS has caused hyperemia and inflammaon in the brain, meninges and liver of treatment groups. Silymarin managed to control the effects of LPS stress on the second generaon (received LPS when they were fetus) in a dose dependent manner. Stresses of mothers during pregnancy can alter in normal physiology of the offspring’s and increase the probability of illness in them in the future. These mothers and their liers has an increased level of proinflammatory cytokines in their serum. Silymarin can be useful for protecng the offsprings from LPS effects in the future life. Keywords: Brain, liver, LPS, mice, offspring, silymarin Effects of Silymarin after Maternal Exposure to LPS on Histopathologic and Immunologic Profiles in Offsprings Amir Ali Shahbazfar*, Peyman Zare, Maryam Mirzaee Department of Pathobiology, Faculty of Veterinary Medicine, University of Tabriz, Tabriz, Iran *Author for correspondence Email: Shahbazfar@tabrizu.ac.ir JOURNAL OF NATURAL REMEDIES 1. Introduction Preparturition and newborn period events like physiologic and immunologic stresses has an important effects on the disorders of a being in the future life even in the life as an adult [1, 2]. Disorders like behavior perturbations, heart problems, atopic diseases and diabetes [3]. Lipopolysaccharides (LPS) are a part of Gram negative bacterial cell wall that are located at the outer part of the bacterial wall [4]. e usage of LPS in high concentration causes anaphylactic shock, chemotaxic responses, cell membrane damage, vascular permeability enhancement, Disseminated Intravascular Coagulopathy(DIC), leukopenia, decrease in phagocytosis, secondary leukocytosis, thrombocytopenia, hypocalcemia, decrease in blood pressure and…..LPS can cause immense disorder in body tissues [4, 5]. It can be a mitogenic factor for B lymphocytes that cause polyclonal increase in their number [6]. It causes Interleukin-1 (IL-1) and Tumor