Introduction: During pregnancy, several maternal metabolic adaptations occur. One of these is the significant changes in lipid metabolism which contribute to the nutrient balance of the fetal-placental unit, essential for fetal development and lactation. Methods: In this study, serum concentration of different fatty acids in healthy pregnant women and three months postpartum were determined by capillary gas chromatography and compared to healthy non-pregnant women and men. Differences between groups were assessed with one-way analyses of variance and the post hoc Tukey-HSD test for multiple comparisons. The Mann-Whitney U test was used when a variable was not normally distributed. Results: The results showed that serum levels of these maternal fatty acids increased significantly from the middle until the end of pregnancy compared to non-pregnant women and decreased at postpartum. Additionally, serum levels of total, saturated, monounsaturated, poly-unsaturated and TRAN¿s fatty acids were significantly elevated in healthy non-pregnant women when compared with men. Conclusion: There are significant differences in the lipid profiles among pregnant and non-pregnant women and men, with a decrease in the serum profile of all fatty acids in the postpartum period.