Abstract Plants that contain pyrrolizidine alkaloids (PAs) have been reported as contaminants of pastures and food, as well as being used in herbal medicine. PAs are responsible for poisoning events in livestock and human beings. The aim of this present study was to evaluate effects of prenatal exposure to integerrimine N-oxide, the main PA found in the butanolic residue (BR) of Senecio brasiliensis, on both physical and behavioral parameters of Wistar rat offspring. The toxicity and maternal behavior were also evaluated. For this, pregnant Wistar rats received integerrimine N-oxide from the BR of Senecio brasiliensis, by gavage, on gestational days 6–20 (during organogenesis and fetal development period) at doses of 3, 6 and 9mg/kg. During treatment, maternal body weight gain, and food and water intake were evaluated. After parturition, maternal behavior and aggressive maternal behavior were analyzed. In addition, physical development and behavioral assessments were observed in both male and female pups. Results showed that prenatal exposure to integerrimine N-oxide of S. brasiliensis induced maternal toxicity, impairment in maternal behavior and aggressive maternal behavior, mainly in the highest dose group. Between sexes comparison of pups showed loss of body weight, delayed physical development such as pinna detachment, hair growth, eruption of incisor teeth, eye and vaginal openings. These pups also showed a delay of palmar grasp, surface righting reflex, negative geotaxis and auditory startle reflexes. Thus, prenatal exposure to integerrimine N-oxide induces maternal toxicity, impairment of maternal care and delayed in physical and behavioral development of the offspring.