Evidence suggests that prenatal maternal immunological stress is associated with an increased risk of neurological and psychiatric disorders in the developing offspring. Protecting the embryo during this critical period of neurodevelopment, when the brain is especially vulnerable, is therefore crucial. Polyphenols, with their antioxidant and anti-inflammatory properties, offer promising therapeutic approaches. This study demonstrated a series of behavioral changes induced by maternal immune activation (MIA) triggered by an antigenic solution derived from the H1N1 virus. These changes include significant differences in anxiety and risk assessment behaviors, increased immobility in the forced swim test, impairments in memory and object recognition, and social deficits resembling autism. The phenolic compound resveratrol (RSV) was evaluated for its in vitro antioxidant capacity and characterized using infrared spectroscopy. Administering RSV from embryonic day 14 (E14) to embrionyc day 19 (E19) during MIA effectively reduced its harmful effects on the offspring. This was evidenced by a significant restoration of social behaviors, memory, and recognition, as well as anxiolytic and antidepressant effects in the adult offspring. These findings contribute to new therapeutic strategies for preventing psychiatric disorders associated with neurodevelopmental stressors.