Background/Objectives: Diets high in simple carbohydrates and saturated fats, commonly consumed in Westernized countries, have been linked to a greater predisposition to metabolic disorders, which are partly attributed to oxidative stress. This study aimed to investigate the impact of an obesogenic diet consumed during the pregnancy and lactation periods on hepatic metabolism and REDOX balance in rats. Methods: Sixteen pregnant Wistar rats were divided into two groups: control (CD), which received a vivarium diet, and obesogenic (OD), which received an obesogenic diet (high-fat diet plus condensed milk), from early pregnancy to late lactation. Thirty-six hours after weaning, the rats were euthanized, and blood, adipose tissue, and liver samples were collected for analysis. Results: These results demonstrate that exposure to an obesogenic diet during pregnancy and lactation in rats leads to adverse changes in hepatic metabolic, inflammatory, and REDOX balance. This experimental animal model serves as a valuable tool for investigating the mechanisms of metabolic dysfunction associated with diets that mimic human eating habits. However, it is essential to note that these findings pertain to an experimental model and therefore require validation in clinical studies to confirm their relevance and applicability in human health. Conclusions: The consumption of an obesogenic diet during pregnancy and lactation in rats induces adverse alterations in hepatic metabolic, inflammatory, and redox homeostasis. This animal model helps investigate the mechanisms of metabolic dysfunctions associated with human dietary habits. However, these findings still need to be confirmed in clinical studies to verify their relevance in humans.