Objectives <p>This work aimed to investigate the impact of folic acid or multivitamin containing folic acid supplementation during pregnancy on morphology and mineral content of enamel structure in deciduous teeth.</p> Materials and methods <p>54 exfoliating deciduous upper central incisors were extracted from children between the ages of 6 and 8. Teeth were divided according to the maternal use of micronutrients into three groups (<i>n</i> = 18), group I: no use; group II: folic acid; and group III: multivitamin containing folic acid. Specimens’ ultrastructure was examined by scanning electron microscope (SEM). Elemental analysis was done using energy-dispersive X-ray spectroscopy (EDX), then statistical evaluation was conducted.</p> Results <p>SEM analysis revealed a uniform enamel surface morphology, indicating a level of resistance to normal physiological enamel wear in groups II and III in contrast to group I. These findings were affirmed by EDX assessment where enamel surface revealed statistically significant higher values for calcium, and phosphorus in groups II and III relative to group I. Additionally, carbon content revealed statistically significant higher values in group I than those of groups II and III, suggesting more susceptibility of hydroxyapatite crystals to dissolution in group Ι.</p> Conclusion <p>Maternal micronutrients supplementation was linked with the preservation of enamel structure in primary teeth. This indicates enhanced enamel resistance to mineral loss during normal physiological dental wear. The findings of this preliminary study highlighted the importance of prenatal multivitamin supplementation as a strategy in preventive dentistry.</p>