Mirtha is a distinctive girls' name in United States, ranking #14421 in 2000 with 6 recorded births. The name reached its all-time peak in 2001 with 14 births ranking #7609. Since 1996, the popularity has decreased by 45.5%. In 2000, approximately 1 in every 302,662 girls born was named Mirtha. FALLING Recent data shows the name is currently falling.