RESUMEN
Teratomas are neoplasms arising from germ cells and encompass tissues derived from two or more embryonic germ layers, including ectoderm, mesoderm, and endoderm. These tumours typically localize along the midline or in paramedian positions and can manifest as gonadal (20%) or extragonadal (80%) entities. Although gonadal teratomas are uncommon, they represent the predominant type of gonadal tumour in the paediatric population. They comprise approximately 20-25% of all ovarian tumours in females and about 3-5% of all testicular tumours in males. Ovarian teratomas exhibit a higher incidence in early childhood and adolescence, whereas testicular teratomas are more prevalent during the first three months of life and between the ages of 15 and 19. While the majority of paediatric gonadal teratomas are benign, malignant or mixed variants may also arise, necessitating more aggressive therapeutic interventions.