Sylvia Úrsula Poll Ahrens[1] (born September 24, 1970 in Managua, Nicaragua) is an Olympic medalist and a national record holding swimmer from Costa Rica.

Her parents were Germans and they settled in Nicaragua where Sylvia and her younger sister Claudia were born.

After the 1972 Nicaragua earthquake and rising political tensions, Sylvia's parents decided to move south to Costa Rica only shortly after Claudia's birth.

She, her sister Claudia, and their mother are not related to Marlene Ahrens, another Olympic athlete and medalist and another Latin American-born daughter of German settlers.

Sylvia Poll is a famous backstroker and freestyle swimmer for Costa Rica, who won the silver medal in the Swimming at the 1988 Summer Olympics Women's 200 meter freestyle at the 1988 Summer Olympics in Seoul, South Korea.