Examination of Fasciola hepatica (Linnaeus, 1758) worms taken from infected bovine livers in Puerto rico revealed the presence of flukes whose ovarian positions vary. In the majority of the flukes observed (88%), the ovary was dextral to the centrally located ootype. In the second group of flukes (8%), the ovary was sinistral to the ootype, and a still smaller group (4%) showed two ovarian branches emerging from a single oviduct trunk anterior to the ootype. This study revealed that in a population of 2,100 F. hepatica flukes the dextral ovarian position was predominant. The sinistral and bifurcated ovarian positions were in the minority. Additional studies are needed to determine the genetic stability of the variations.Examinando la posición del ovario de 2,100 especímenes de Fasciola hepatica se observó que el 88% de los parásitos presentaron las ramificaciones del ovario en posición dextral, el 8% sinestral y el 4% con ramificaciones en ambos lados. El punto de referencia se relacionó con el ootipo, localizado en el tercio anterior y central del parásito, visto ventralmente. Se requieren estudios genéticos adicionales para establecer su estabilidad o variación genética.