Cynthia is a moderately popular girls' name in United States, ranking #239 in 2006 with 1,420 recorded births. The name reached its all-time peak in 1996 with 3,189 births ranking #101. Since 1996, the popularity has decreased by 55.5%. In 2006, approximately 1 in every 1,339 girls born was named Cynthia. FALLING Recent data shows the name is currently falling.